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1.
Eur Radiol ; 30(7): 3641-3649, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32125513

RESUMO

OBJECTIVES: To evaluate the diagnostic test accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT), whole-body magnetic resonance imaging (WB-MRI), and whole-body diffusion-weighted imaging (WB-DWI) for the detection of metastases in patients with non-small cell lung cancer (NSCLC). METHODS: MEDLINE, Embase, and Cochrane Library databases were searched up to June 2019. Studies were selected if they reported data that could be used to construct contingency tables to compare 18F-FDG PET/CT, WB-MRI, and WB-DWI. Two authors independently extracted data on study characteristics and assessed methodological quality using the Quality Assessment of Diagnostic Accuracy Studies. Forest plots were generated for sensitivity and specificity of 18F-FDG PET/CT, WB-MRI, and whole-body diffusion-weighted imaging (WB-DWI). Summary receiver operating characteristic plots were created. RESULTS: The 4 studies meeting inclusion criteria had a total of 564 patients and 559 lesions, 233 of which were metastases. In studies of 18F-FDG PET/CT, the pooled estimates of sensitivity and specificity were 0.83 (95% confidence interval [CI], 0.54-0.95) and 0.93 (95% CI, 0.87-0.96), respectively. For WB-MRI, pooled sensitivity was 0.92 (95% CI, 0.18-1.00) and pooled specificity was 0.93 (95% CI, 0.85-0.95). Pooled sensitivity and specificity for WB-DWI were 0.78 (95% CI, 0.46-0.93) and 0.91 (95% CI, 0.79-0.96), respectively. There was no statistical difference between the diagnostic odds ratio of WB-MRI and WB-DWI compared with that of PET/CT (p = 0.186 for WB-DWI; p = 0.638 for WB-MRI). CONCLUSION: WB-MRI and DWI are radiation-free alternatives with comparable diagnostic performance to 18F-FDG PET/CT for M staging of NSCLC. KEY POINTS: • Whole-body MRI with or without diffusion-weighted imaging has a high accuracy for the diagnostic evaluation of metastases in patients with non-small cell lung cancer. • Whole-body MRI may be used as a non-invasive and radiation-free alternative to positron emission tomography with CT with similar diagnostic performance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Imagem Corporal Total/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Fluordesoxiglucose F18 , Humanos , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade
2.
Radiology ; 290(2): 525-534, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30480492

RESUMO

Purpose To perform a meta-analysis of the literature to compare the diagnostic performance of fluorine 18 fluorodeoxyglucose PET/CT and diffusion-weighted (DW) MRI in the differentiation of malignant and benign pulmonary nodules and masses. Materials and Methods Published English-language studies on the diagnostic accuracy of PET/CT and/or DW MRI in the characterization of pulmonary lesions were searched in relevant databases through December 2017. The primary focus was on studies in which joint DW MRI and PET/CT were performed in the entire study population, to reduce interstudy heterogeneity. For DW MRI, lesion-to-spinal cord signal intensity ratio and apparent diffusion coefficient were evaluated; for PET/CT, maximum standard uptake value was evaluated. The pooled sensitivities, specificities, diagnostic odds ratios, and areas under the receiver operating characteristic curve (AUCs) for PET/CT and DW MRI were determined along with 95% confidence intervals (CIs). Results Thirty-seven studies met the inclusion criteria, with a total of 4224 participants and 4463 lesions (3090 malignant lesions [69.2%]). In the primary analysis of joint DW MRI and PET/CT studies (n = 6), DW MRI had a pooled sensitivity and specificity of 83% (95% CI: 75%, 89%) and 91% (95% CI: 80%, 96%), respectively, compared with 78% (95% CI: 70%, 84%) (P = .01 vs DW MRI) and 81% (95% CI: 72%, 88%) (P = .056 vs DW MRI) for PET/CT. DW MRI yielded an AUC of 0.93 (95% CI: 0.90, 0.95), versus 0.86 (95% CI: 0.83, 0.89) for PET/CT (P = .001). The diagnostic odds ratio of DW MRI (50 [95% CI: 19, 132]) was superior to that of PET/CT (15 [95% CI: 7, 32]) (P = .006). Conclusion The diagnostic performance of diffusion-weighted MRI is comparable or superior to that of fluorine 18 fluorodeoxyglucose PET/CT in the differentiation of malignant and benign pulmonary lesions. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by Schiebler in this issue.


Assuntos
Diagnóstico por Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Diagnóstico Diferencial , Fluordesoxiglucose F18/uso terapêutico , Humanos , Sensibilidade e Especificidade
3.
Lung ; 197(3): 259-265, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30900014

RESUMO

The lung acinus is the most distal portion of the airway responsible for the gas exchange. The normal acini are not visible on conventional computed tomography (CT), but the advent of micro-CT improved the understanding of the microarchitecture of healthy acini. The comprehension of the acinar architecture is pivotal for the understanding of CT findings of diseases that involve the acini. Centriacinar emphysema, for example, presents as round areas of low attenuation due to the destruction of the most central acini with compensatory enlargement of proximal acini due to alveolar wall destruction. In pulmonary fibrosis, intralobular septal fibrosis manifests as acinar wall thickening with an overlap of acinar collapse and compensatory dilation of surrounding acini constituting the cystic disease typical of the usual interstitial pneumonia pattern. This is a state-of-the-art review to describe the acinar structure from the micro-CT perspective and display how the comprehension of the acinar structure can aid in the interpretation of its microarchitecture disruption on conventional CT.


Assuntos
Pulmão/diagnóstico por imagem , Alvéolos Pulmonares/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X , Microtomografia por Raio-X
4.
J Cell Mol Med ; 19(6): 1253-61, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25854285

RESUMO

Patients undergoing mechanical ventilation (MV) often experience respiratory muscle dysfunction, which complicates the weaning process. There is no simple means to predict or diagnose respiratory muscle dysfunction because diagnosis depends on measurements in muscle diaphragmatic fibre. As oxidative stress is a key mechanism contributing to MV-induced respiratory muscle dysfunction, the aim of this study was to determine if differences in blood measures of oxidative stress in patients who had success and failure in a spontaneous breathing trial (SBT) could be used to predict the outcome of MV. This was a prospective analysis of MV-dependent patients (≥72 hrs; n = 34) undergoing a standard weaning protocol. Clinical, laboratory and oxidative stress analyses were performed. Measurements were made on blood samples taken at three time-points: immediately before the trial, 30 min. into the trial in weaning success (WS) patients, or immediately before return to MV in weaning failure (WF) patients, and 6 hrs after the trial. We found that blood measures of oxidative stress distinguished patients who would experience WF from patients who would experience WS. Before SBT, WF patients presented higher oxidative damage in lipids and higher antioxidant levels and decreased nitric oxide concentrations. The observed differences in measures between WF and WS patients persisted throughout and after the weaning trial. In conclusion, WF may be predicted based on higher malondialdehyde, higher vitamin C and lower nitric oxide concentration in plasma.


Assuntos
Biomarcadores/sangue , Estresse Oxidativo , Respiração Artificial/métodos , Desmame do Respirador/métodos , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/sangue , Catalase/sangue , Feminino , Glutationa/sangue , Dissulfeto de Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Nitritos/sangue , Avaliação de Resultados em Cuidados de Saúde/métodos , Valor Preditivo dos Testes , Superóxido Dismutase/sangue
5.
Br J Radiol ; 96(1146): 20220889, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37066809

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy of MRI-hysterosalpingogram (HSG) with semiquantitative dynamic contrast-enhanced perfusion, against the virtual multislice CT hysterosalpingogram (VHSG) as a reference standard. METHODS AND MATERIALS: In this prospective study, 26 women (age >18 years) searching for infertility causes and with VHSG physician request. Thereafter, the assessment performance of both techniques was determined by two reader analyses. k statistics were used for the assessment of tubal patency. Receiver operating characteristic (ROC) analysis was used to compare the capability for tubal patency assessment between both exams on a per-patient and per-tube basis. The McNemar test was used to compare the diagnostic accuracy measures. RESULTS: Tubal patency, uterine morphological, ovarian, and extrauterine abnormalities were evaluated through both exams in all 26 women. There was no significant difference between diagnostic performance measurements between the methods. The ROC curve of VHSG was 0.852 for both per-patient and per-tube analyses, and one and 0.938 for MRI-HSG. Sensitivity and specificity for per-patient and per-tube for VHSG were 95.2 and 97.7, 80 and 87.5%, and for MRI-HSG 100% for both analyses and 100 and 87.5%, respectively. CONCLUSION: This study demonstrates the feasibility of diagnosing tubal patency through MRI, using a semi-quantitative dynamic contrast-enhanced perfusion sequence, and the satisfactory diagnosing of the uterine morphology, ovarian abnormalities, and ovarian and deep endometriosis. ADVANCES IN KNOWLEDGE: Multiparametric MRI with a perfusion real-time sequence as a HSG method can be used in the evaluation not only for uterine and ovarian abnormilities but also tubal patency.


Assuntos
Doenças das Tubas Uterinas , Infertilidade Feminina , Imageamento por Ressonância Magnética Multiparamétrica , Feminino , Humanos , Adolescente , Histerossalpingografia/efeitos adversos , Histerossalpingografia/métodos , Estudos Prospectivos , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/etiologia , Doenças das Tubas Uterinas/diagnóstico por imagem , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X/efeitos adversos
6.
ERJ Open Res ; 8(2)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35747230

RESUMO

Purpose: The aim of this study was to analyse and quantify the prevalence of six comorbidities from lung cancer screening (LCS) on computed tomography (CT) scans of patients from developing countries. Methods: For this retrospective study, low-dose CT scans (n=775) were examined from patients who underwent LCS in a tertiary hospital between 2016 and 2020. An age- and sex-matched control group was obtained for comparison (n=370). Using the software, coronary artery calcification (CAC), the skeletal muscle area, interstitial lung abnormalities, emphysema, osteoporosis and hepatic steatosis were accessed. Clinical characteristics of each participant were identified. A t-test and Chi-squared test were used to examine differences between these values. Interclass correlation coefficients (ICCs) and interobserver agreement (assessed by calculating kappa coefficients) were calculated to assess the correlation of measures interpreted by two observers. p-values <0.05 were considered significant. Results: One or more comorbidities were identified in 86.6% of the patients and in 40% of the controls. The most prevalent comorbidity was osteoporosis, present in 44.2% of patients and in 24.8% of controls. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46% of cases, respectively. The kappa coefficient for CAC was 0.906 (p<0.001). ICCs for measures of liver, spleen and bone density were 0.88, 0.93 and 0.96, respectively (p<0.001). Conclusions: CT data acquired during LCS led to the identification of previously undiagnosed comorbidities. The LCS is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatment.

7.
Radiol Bras ; 54(5): 329-335, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34602669

RESUMO

Whole-body magnetic resonance imaging (WB-MRI) is a noninvasive imaging method that can be used to diagnose and stage tumors, as well as to assess therapeutic responses in oncology. The objective of this meta-analysis was to evaluate the accuracy of WB-MRI for the diagnosis of metastases in pediatric patients. The following electronic databases were searched: Medline, Embase, Cochrane Central Register of Controlled Trials, Scientific Electronic Library Online, Latin-American and Caribbean Health Sciences Literature, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and ClinicalTrials.gov. All of the selected studies included children and adolescents with histopathological confirmation of a primary tumor. Collectively, the studies included 118 patients ranging in age from 7 months to 19 years. The pooled sensitivity and specificity of WB-MRI were, respectively, 0.964 (95% CI: 0.944-0.978; I 2 = 0%) and 0.902 (95% CI: 0.882-0.919; I 2 = 98.4%), with an area under the curve (AUC) of 0.991. We found that WB-MRI had good accuracy for the diagnosis of metastases in pediatric patients and could therefore provide an alternative to complete the staging of tumors in such patients, being a safer option because it does not involve the use of ionizing radiation.


A ressonância magnética de corpo inteiro (WB-MRI) é um método de imagem não invasivo que pode ser usado para diagnosticar, estadiar e avaliar a resposta terapêutica em oncologia. O objetivo desta meta-análise foi avaliar a precisão do diagnóstico de WB- MRI no diagnóstico de metástases em crianças. Foram pesquisadas as seguintes bastes de dados: Medline, Embase, Cochrane Central Register of Controlled Trials, Scientific Electronic Library Online, Latin-American and Caribbean Health Sciences Literature, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and ClinicalTrials.gov. Todos os estudos incluíram crianças e adolescentes com prova histopatológica de um tumor original. Os estudos selecionados incluíram 118 pacientes com idade variando de 7 meses a 19 anos. A sensibilidade e especificidade combinadas de WB-MRI foram, respectivamente, 0,964 (IC 95%: 0,944-0,978; I 2 = 0%) e 0,902 (IC 95%: 0,882-0,919; I 2 = 98,4%), com AUC de 0,991. A WB-MRI tem uma boa precisão para o diagnóstico de metástases em pediatria e pode potencialmente fornecer um método alternativo não ionizante mais seguro para completar o estadiamento da doença maligna em crianças.

8.
Radiol Bras ; 54(4): 225-231, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393288

RESUMO

OBJECTIVE: To establish the diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) in discriminating malignant from non-malignant thoracic lymph nodes. MATERIALS AND METHODS: This was a meta-analysis involving systematic searches of the MEDLINE, EMBASE, and Web of Science databases up through April 2020. Studies reporting thoracic DWI and lymph node evaluation were included. The pooled sensitivity, specificity, diagnostic odds ratio, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated. RESULTS: We evaluated six studies, involving a collective total of 356 mediastinal lymph nodes in 214 patients. Thoracic DWI had a pooled sensitivity and specificity of 92% (95% confidence interval [95% CI]: 71-98%) and 93% (95% CI: 79-98%), respectively. The positive and negative likelihood ratios were 13.2 (95% CI: 4.0-43.8) and 0.09 (95% CI: 0.02-0.36), respectively. The diagnostic odds ratio was 149 (95% CI: 18-1,243), and the AUC was 0.97 (95% CI: 0.95-0.98). CONCLUSION: DWI is a reproducible technique and has demonstrated high accuracy for differentiating between malignant and benign states in thoracic lymph nodes.


OBJETIVO: Uma meta-análise foi realizada para estabelecer o desempenho diagnóstico da ressonância magnética com imagem ponderada em difusão (DWI) na discriminação de linfonodos torácicos malignos de benignos. MATERIAIS E MÉTODOS: MEDLINE, EMBASE e Web of Science foram sistematicamente pesquisados até abril de 2020. Foram incluídos estudos que relatavam o uso de DWI na avaliação de linfonodos torácicos. Sensibilidade, especificidade, razão de chances de diagnóstico, valores preditivos positivos e negativos e área sob a curva (AUC) foram calculados. RESULTADOS: Foram encontrados 356 linfonodos mediastinais de 214 pacientes nos seis estudos incluídos. DWI produziu sensibilidade e especificidade combinadas de 92% (intervalo de confiança 95% [IC 95%]: 71-98%) e 93% (IC 95%: 79-98%), respectivamente. A razão de verossimilhança positiva foi de 13,2 (IC 95%: 4,0-43,8), a razão de verossimilhança negativa foi de 0,09 (IC 95%: 0,02-0,36); A razão de chances de diagnóstico foi de 149 (IC 95%: 18-1.243). A DWI teve uma AUC de 0,97 (IC 95%: 0,95-0,98). CONCLUSÃO: DWI é uma técnica reprodutível que demonstrou alta acurácia na diferenciação de estados malignos e benignos nos linfonodos torácicos.

9.
J Bras Pneumol ; 47(2): e20200055, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33825792

RESUMO

OBJECTIVE: Evaluation of enlarged mediastinal lymph nodes is crucial for patient management. Malignant lymphoma and sarcoidosis are often difficult to differentiate. Our objective was to determine the diagnostic accuracy of MRI for differentiating between sarcoidosis and malignant lymphoma. METHODS: This was a retrospective study involving 47 patients who underwent chest MRI and were diagnosed with one of the diseases between 2017 and 2019. T1, T2, and diffusion-weighted signal intensity were measured. Apparent diffusion coefficients (ADCs) and T2 ratios were calculated. The diagnostic performance of MRI was determined by ROC analysis. RESULTS: Mean T2 ratio was significantly lower in the sarcoidosis group than in the lymphoma group (p = 0.009). The T2-ratio cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 7.1, with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 58.3%, 95.6%, 76.5%, 93.3%, and 68.7%, respectively. The mean ADC was significantly lower in the lymphoma group than in the sarcoidosis group (p = 0.002). The ADC cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 1.205, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 87.5%, 82.6%, 85.1%, 84.0% and 86.3%, respectively. No significant differences were found between the two groups regarding T1 signal intensity, T2 signal intensity, and lymph node diameter. CONCLUSIONS: MRI parameters such as ADC, diffusion, and T2 ratio can be useful in the differentiation between sarcoidosis and lymphoma in the evaluation of enlarged lymph nodes.


Assuntos
Linfoma , Sarcoidose , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Linfoma/diagnóstico por imagem , Estudos Retrospectivos , Sarcoidose/diagnóstico por imagem , Sensibilidade e Especificidade
10.
Mycopathologia ; 170(1): 11-20, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20229037

RESUMO

In the course of an infection, the formation of reactive oxygen species by phagocytes and the antioxidant defense mechanisms of microorganisms play a crucial role in pathogenesis. In this study, isolates representing 8 pathogenic Candida species-Candida albicans, Candida dubliniensis, Candida famata, Candida glabrata, Candida guilliermondii, Candida krusei, Candida parapsilosis and Candida tropicalis-were compared with regard to their resistance to oxidative stress in vitro. We evaluated degree of resistance, induction of oxidative damage, capacity to adapt, and induction of antioxidant enzymes. The species showed variable sensitivity to oxidative attack. C. albicans, C. glabrata, and C. krusei were more resistant to oxidative stress under the conditions tested; C. parapsilosis and C. tropicalis presented medium resistance; and C. dubliniensis, C. famata, and C. guilliermondii were more sensitive. The overall greater resistance to oxidative stress of C. albicans and C. glabrata may provide an advantage to these species, which are the major causative agents of candidiasis.


Assuntos
Candida/fisiologia , Oxidantes/toxicidade , Estresse Oxidativo , Estresse Fisiológico , Antioxidantes/fisiologia , Candida/efeitos dos fármacos , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Espécies Reativas de Oxigênio/toxicidade
11.
J Bras Pneumol ; 46(3): e20190095, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32321034

RESUMO

OBJECTIVE: To evaluate the health-related quality of life (HRQoL) of children/adolescents with asthma and that of their caregivers, comparing the two. METHODS: This was a systematic review and meta-analysis based on the criteria of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, with a strategy of searching five health-related databases (MEDLINE/PubMed, EMBASE, ScienceDirect, SciELO, and LILACS). We included studies that evaluated the HRQoL of children/adolescents with asthma and that of their caregivers with the Pediatric Asthma Quality of Life Questionnaire and the Pediatric Asthma Caregiver's Quality of Life Questionnaire, respectively, using the total scores and the scores on the domains activity limitation, symptoms (children/adolescents only), and emotional function. RESULTS: We identified 291 articles, and we evaluated 133 of those. A total of 33 articles, collectively including 4,101 subjects, were included in the meta-analysis. An analysis stratified by study design showed no differences between the HRQoL of the caregivers and that of the children/adolescents in the activity limitation domain and in the total score. However, the mean emotional function domain scores were significantly higher (better) among children/adolescents with asthma than among their caregivers in longitudinal studies-Δ = 0.82 (0.21-1.44)-and randomized clinical trials-Δ = 0.52 (0.29-0.79)-although not in cross-sectional studies-Δ = -0.20 (-0.03 to 0.43). CONCLUSIONS: The total HRQoL scores proved to be similar between children/adolescents with asthma and their caregivers. However, the two groups differed in their perception of their emotional function, the caregivers scoring significantly lower than the children/adolescents in that domain.


Assuntos
Asma/psicologia , Cuidadores/psicologia , Qualidade de Vida , Adolescente , Asma/fisiopatologia , Criança , Estudos Transversais , Nível de Saúde , Humanos
12.
Ther Hypothermia Temp Manag ; 9(1): 63-69, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30016204

RESUMO

Ischemia-reperfusion (I/R)-induced oxidative stress is one of the main mechanisms of tissue injury after cardiac arrest (CA). A decrease in antioxidant defenses may contribute to I/R injury. The present study aims to investigate the influence of mild therapeutic hypothermia (MTH) on levels of nonenzymatic antioxidants after CA. We investigated antioxidant levels at 6, 12, 36, and 72 hours after CA in central venous blood samples of patients admitted to intensive care. The sample consisted of 31 patients under controlled normothermia (36°C) and 11 patients treated with 24 hours of MTH (33°C). Erythrocyte glutathione (GSH) levels were elevated by MTH, increasing at 6, 12, 36, and 72 hours after CA in hypothermic patients (mean GSH levels in normothermic patients: 6 hours = 73.89, 12 hours = 56.45, 36 hours = 56.46, 72 hours = 61.80 vs. hypothermic patients: 6 hours = 176.89, 12 hours = 198.78, 36 hours = 186.96, and 72 hours = 173.68 µmol/g of protein). Vitamin C levels decreased significantly at 6 and 12 hours after CA in hypothermic patients (median vitamin C levels in normothermic patients: 6 hours = 7.53, 12 hours = 9.40, 36 hours = 8.56, and 72 hours = 8.51 vs. hypothermic patients: 6 hours = 5.46, 12 hours = 5.44, 36 hours = 6.10, and 72 hours = 5.89 mmol/L), coinciding with the period of therapeutic hypothermia. Vitamin E and nitric oxide levels were not altered by hypothermic treatment. These findings suggest that MTH alters nonenzymatic antioxidants differently, decreasing circulating vitamin C levels during treatment; however, MTH elevates GSH levels, possibly protecting tissues from I/R injury after CA.


Assuntos
Glutationa/sangue , Parada Cardíaca/sangue , Parada Cardíaca/terapia , Hipotermia Induzida/métodos , Idoso , Antioxidantes/metabolismo , Ácido Ascórbico/sangue , Cuidados Críticos , Eritrócitos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Estudos Prospectivos , Vitamina E/sangue
13.
PLoS One ; 13(6): e0199099, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29912927

RESUMO

Movement patterns resembling Lévy walks, often attributed to the execution of an advantageous probabilistic searching strategy, are found in a wide variety of organisms, from cells to human hunter-gatherers. It has been suggested that such movement patterns may be fundamental to how humans interact and experience the world and that they may have arisen early in our genus with the evolution of a hunting and gathering lifestyle. Here we show that Lévy walks are evident in the Me'Phaa of Mexico, in Brazilian Cariri farmers and in Amazonian farmers when gathering firewood, wild fruit and nuts. Around 50% of the search patterns resemble Lévy walks and these are characterized by Lévy exponents close to 1.7. The other search patterns more closely resemble bi-phasic walks. We suggest potential generative mechanisms for the occurrence of these ubiquitous Lévy walks which can be used to guide future studies on human mobility. We show that frequent excursions and meanderings from pre-existing trails can account for our observations.


Assuntos
Atividade Motora , População Rural , Atividades Cotidianas/psicologia , Brasil , Feminino , Humanos , Masculino , México , Caminhada/psicologia
14.
ABC., imagem cardiovasc ; 36(1): e368, abr. 2023. ilus, tab
Artigo em Português | LILACS | ID: biblio-1512933

RESUMO

Fundamento: As calcificações de artérias coronárias (CAC) mostram-se como fator preditivo de doenças cardiovasculares (DCV). A tomografia computadorizada (TC) de tórax com protocolo de aquisição de baixa dose apresenta acurácia na identificação de CAC e propicia achados incidentais dessas calcificações, que são comumente negligenciados. Este estudo analisará a prevalência de achados incidentais de calcificação em artérias coronárias em indivíduos não cardiopatas submetidos à TC de tórax. Métodos: Estudo transversal consecutivo de caráter analítico e descritivo. Foram incluídos indivíduos de ambos os sexos que realizaram TC de tórax por encaminhamento, acima de 18 anos e não cardiopatas. A coleta de dados foi realizada por meio de prontuários e ficha de anamnese auto aplicada. As variáveis referentes às CAC e à extensão do comprometimento foram obtidas a partir da reavaliação das imagens de TC de tórax disponíveis no sistema da instituição. Os exames foram anonimizados e avaliados por dois médicos radiologistas experientes. Considerou-se como estatisticamente significativo p≤0,05. Resultados: Foram analisados 397 exames. Encontrou-se prevalência de calcificações em 176 (44%) dos casos. A existência dessas calcificações coronárias está relacionada à idade (p<0,001). As calcificações possuem relação com o sexo (p = 0,03) com maior razão de chance de desenvolvimento em homens (odds ratio [OR] = 1,55). O tabagismo (p<0,001), o sedentarismo (p<0,001), a hipertensão arterial sistêmica (p<0,001), o diabetes mellitus (p = 0,04) e as dislipidemias (p<0,001) mostraram associação positiva. Conclusão: A prevalência de achados incidentais de CAC foi de 44%; variam em maior número entre leve e grave; maior razão de chance no sexo masculino e aumento da prevalência com a idade. Portanto, a TC de tórax mostra-se um efetivo método para avaliar as CAC, e juntamente com a história clínica do paciente pode ser utilizada para medir os fatores de risco para doenças cardiovasculares e intervir no desfecho do quadro.(AU)


Introduction: Coronary artery calcifications (CAC) are shown to be a predictive factor of cardiovascular diseases. Computed tomography (CT) of the chest with a low-dose acquisition protocol is accurate in identifying CAC and provides incidental findings of these calcifications, which are commonly overlooked. This study will analyze the prevalence of incidental findings of calcification in coronary arteries in non-cardiac individuals undergoing chest CT. Methods: Consecutive cross-sectional study of an analytical and descriptive nature. Individuals of both genders who underwent chest CT by referral, over 18 years of age and without heart disease were included. Data collection was carried out using medical records and a self-applied anamnesis form. The variables referring to the CAC and the extension of the impairment were obtained from the reassessment of the chest CT images available in the institution's system. The exams were anonymized and evaluated by two experienced radiologists. P≤0.05 was considered statistically significant. Results: 397 exams were analyzed. A prevalence of calcifications was found in 176 (44%) of the cases. The existence of these coronary calcifications is related to age (p<0.001). Calcifications are related to gender (p = 0.03) with a higher odds ratio of development in men (odds ratio [OR] = 1.55). Smoking (p<0.001), sedentary lifestyle (p<0.001), systemic arterial hypertension (p<0.001), Diabetes Mellitus (p = 0.04), and dyslipidemia (p<0.001) showed a positive association. Conclusion: The prevalence of incidental CAC findings was 44%; vary in greater numbers between mild and severe; higher odds ratio in males and increased prevalence with age. Therefore, chest CT proves to be an effective method to assess CAC, and together with the patient's clinical history, it can be used to measure risk factors for CVD and intervene in the outcome of the condition.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Achados Incidentais , Calcificação Vascular/fisiopatologia , Calcificação Vascular/prevenção & controle , Calcificação Vascular/diagnóstico por imagem , Tabagismo/etiologia , Dor no Peito/etiologia , Tomografia Computadorizada por Raios X/métodos , Diabetes Mellitus/etiologia , Dispneia/etiologia , Hemoptise/etiologia , Hipertensão/etiologia
15.
Oxid Med Cell Longev ; 2017: 8704352, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553435

RESUMO

After cardiac arrest, organ damage consequent to ischemia-reperfusion has been attributed to oxidative stress. Mild therapeutic hypothermia has been applied to reduce this damage, and it may reduce oxidative damage as well. This study aimed to compare oxidative damage and antioxidant defenses in patients treated with controlled normothermia versus mild therapeutic hypothermia during postcardiac arrest syndrome. The sample consisted of 31 patients under controlled normothermia (36°C) and 11 patients treated with 24 h mild therapeutic hypothermia (33°C), victims of in- or out-of-hospital cardiac arrest. Parameters were assessed at 6, 12, 36, and 72 h after cardiac arrest in the central venous blood samples. Hypothermic and normothermic patients had similar S100B levels, a biomarker of brain injury. Xanthine oxidase activity is similar between hypothermic and normothermic patients; however, it decreases posthypothermia treatment. Xanthine oxidase activity is positively correlated with lactate and S100B and inversely correlated with pH, calcium, and sodium levels. Hypothermia reduces malondialdehyde and protein carbonyl levels, markers of oxidative damage. Concomitantly, hypothermia increases the activity of erythrocyte antioxidant enzymes superoxide dismutase, glutathione peroxidase, and glutathione S-transferase while decreasing the activity of serum paraoxonase-1. These findings suggest that mild therapeutic hypothermia reduces oxidative damage and alters antioxidant defenses in postcardiac arrest patients.


Assuntos
Antioxidantes/metabolismo , Parada Cardíaca/patologia , Parada Cardíaca/terapia , Hipotermia Induzida , Estresse Oxidativo , Biomarcadores/metabolismo , Encéfalo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar , Resultado do Tratamento , Xantina Oxidase/metabolismo
16.
Radiol. bras ; 54(4): 225-231, July-Aug. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1287757

RESUMO

Abstract Objective: To establish the diagnostic performance of diffusion-weighted magnetic resonance imaging (DWI) in discriminating malignant from non-malignant thoracic lymph nodes. Materials and Methods: This was a meta-analysis involving systematic searches of the MEDLINE, EMBASE, and Web of Science databases up through April 2020. Studies reporting thoracic DWI and lymph node evaluation were included. The pooled sensitivity, specificity, diagnostic odds ratio, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) were calculated. Results: We evaluated six studies, involving a collective total of 356 mediastinal lymph nodes in 214 patients. Thoracic DWI had a pooled sensitivity and specificity of 92% (95% confidence interval [95% CI]: 71-98%) and 93% (95% CI: 79-98%), respectively. The positive and negative likelihood ratios were 13.2 (95% CI: 4.0-43.8) and 0.09 (95% CI: 0.02-0.36), respectively. The diagnostic odds ratio was 149 (95% CI: 18-1,243), and the AUC was 0.97 (95% CI: 0.95-0.98). Conclusion: DWI is a reproducible technique and has demonstrated high accuracy for differentiating between malignant and benign states in thoracic lymph nodes.


Resumo Objetivo: Uma meta-análise foi realizada para estabelecer o desempenho diagnóstico da ressonância magnética com imagem ponderada em difusão (DWI) na discriminação de linfonodos torácicos malignos de benignos. Materiais e Métodos: MEDLINE, EMBASE e Web of Science foram sistematicamente pesquisados até abril de 2020. Foram incluídos estudos que relatavam o uso de DWI na avaliação de linfonodos torácicos. Sensibilidade, especificidade, razão de chances de diagnóstico, valores preditivos positivos e negativos e área sob a curva (AUC) foram calculados. Resultados: Foram encontrados 356 linfonodos mediastinais de 214 pacientes nos seis estudos incluídos. DWI produziu sensibilidade e especificidade combinadas de 92% (intervalo de confiança 95% [IC 95%]: 71-98%) e 93% (IC 95%: 79-98%), respectivamente. A razão de verossimilhança positiva foi de 13,2 (IC 95%: 4,0-43,8), a razão de verossimilhança negativa foi de 0,09 (IC 95%: 0,02-0,36); A razão de chances de diagnóstico foi de 149 (IC 95%: 18-1.243). A DWI teve uma AUC de 0,97 (IC 95%: 0,95-0,98). Conclusão: DWI é uma técnica reprodutível que demonstrou alta acurácia na diferenciação de estados malignos e benignos nos linfonodos torácicos.

17.
J. bras. pneumol ; 47(2): e20200055, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1180801

RESUMO

ABSTRACT Objective: Evaluation of enlarged mediastinal lymph nodes is crucial for patient management. Malignant lymphoma and sarcoidosis are often difficult to differentiate. Our objective was to determine the diagnostic accuracy of MRI for differentiating between sarcoidosis and malignant lymphoma. Methods: This was a retrospective study involving 47 patients who underwent chest MRI and were diagnosed with one of the diseases between 2017 and 2019. T1, T2, and diffusion-weighted signal intensity were measured. Apparent diffusion coefficients (ADCs) and T2 ratios were calculated. The diagnostic performance of MRI was determined by ROC analysis. Results: Mean T2 ratio was significantly lower in the sarcoidosis group than in the lymphoma group (p = 0.009). The T2-ratio cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 7.1, with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 58.3%, 95.6%, 76.5%, 93.3%, and 68.7%, respectively. The mean ADC was significantly lower in the lymphoma group than in the sarcoidosis group (p = 0.002). The ADC cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 1.205, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 87.5%, 82.6%, 85.1%, 84.0% and 86.3%, respectively. No significant differences were found between the two groups regarding T1 signal intensity, T2 signal intensity, and lymph node diameter. Conclusions: MRI parameters such as ADC, diffusion, and T2 ratio can be useful in the differentiation between sarcoidosis and lymphoma in the evaluation of enlarged lymph nodes.


RESUMO Objetivo: A avaliação de linfonodomegalias mediastinais é crucial para o manejo dos pacientes. O linfoma maligno e a sarcoidose costumam ser difíceis de diferenciar. Nosso objetivo foi determinar a precisão diagnóstica da RMN para diferenciar sarcoidose de linfoma maligno. Métodos: Estudo retrospectivo com 47 pacientes submetidos a RMN de tórax e diagnosticados com uma das doenças entre 2017 e 2019. Foi medida a intensidade do sinal em T1, T2 e difusão. Foram calculados o coeficiente de difusão aparente (ADC, do inglês apparent diffusion coefficient) e a razão T2. O desempenho diagnóstico da RMN foi determinado pela análise da curva ROC. Resultados: A média da razão T2 foi significativamente menor no grupo sarcoidose que no grupo linfoma (p = 0,009). A razão T2 = 7,1 foi o melhor valor de corte para diferenciar linfonodomegalias relacionadas com linfoma daquelas relacionadas com sarcoidose, com sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e precisão de 58,3%, 95,6%, 76,5%, 93,3% e 68,7%, respectivamente. A média do ADC foi significativamente menor no grupo linfoma que no grupo sarcoidose (p = 0,002). O ADC = 1,205 foi o melhor valor de corte para diferenciar linfonodomegalias relacionadas com linfoma daquelas relacionadas com sarcoidose, com sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e precisão de 87,5%, 82,6%, 85,1%, 84,0% e 86,3%, respectivamente. Não houve diferença significativa entre os grupos quanto à intensidade do sinal em T1, intensidade do sinal em T2 e diâmetro dos linfonodos. Conclusões: Parâmetros de RMN como ADC, difusão e razão T2 podem ser úteis na diferenciação entre sarcoidose e linfoma na avaliação de linfonodomegalias.


Assuntos
Humanos , Sarcoidose/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade , Linfonodos/diagnóstico por imagem , Metástase Linfática
18.
Radiol. bras ; 54(5): 329-335, Sept.-Oct. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1340574

RESUMO

Abstract Whole-body magnetic resonance imaging (WB-MRI) is a noninvasive imaging method that can be used to diagnose and stage tumors, as well as to assess therapeutic responses in oncology. The objective of this meta-analysis was to evaluate the accuracy of WB-MRI for the diagnosis of metastases in pediatric patients. The following electronic databases were searched: Medline, Embase, Cochrane Central Register of Controlled Trials, Scientific Electronic Library Online, Latin-American and Caribbean Health Sciences Literature, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and ClinicalTrials.gov. All of the selected studies included children and adolescents with histopathological confirmation of a primary tumor. Collectively, the studies included 118 patients ranging in age from 7 months to 19 years. The pooled sensitivity and specificity of WB-MRI were, respectively, 0.964 (95% CI: 0.944-0.978; I2 = 0%) and 0.902 (95% CI: 0.882-0.919; I2 = 98.4%), with an area under the curve (AUC) of 0.991. We found that WB-MRI had good accuracy for the diagnosis of metastases in pediatric patients and could therefore provide an alternative to complete the staging of tumors in such patients, being a safer option because it does not involve the use of ionizing radiation.


Resumo A ressonância magnética de corpo inteiro (WB-MRI) é um método de imagem não invasivo que pode ser usado para diagnosticar, estadiar e avaliar a resposta terapêutica em oncologia. O objetivo desta meta-análise foi avaliar a precisão do diagnóstico de WB- MRI no diagnóstico de metástases em crianças. Foram pesquisadas as seguintes bastes de dados: Medline, Embase, Cochrane Central Register of Controlled Trials, Scientific Electronic Library Online, Latin-American and Caribbean Health Sciences Literature, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and ClinicalTrials.gov. Todos os estudos incluíram crianças e adolescentes com prova histopatológica de um tumor original. Os estudos selecionados incluíram 118 pacientes com idade variando de 7 meses a 19 anos. A sensibilidade e especificidade combinadas de WB-MRI foram, respectivamente, 0,964 (IC 95%: 0,944-0,978; I2 = 0%) e 0,902 (IC 95%: 0,882-0,919; I2 = 98,4%), com AUC de 0,991. A WB-MRI tem uma boa precisão para o diagnóstico de metástases em pediatria e pode potencialmente fornecer um método alternativo não ionizante mais seguro para completar o estadiamento da doença maligna em crianças.

19.
J. bras. pneumol ; 46(3): e20190095, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1101263

RESUMO

ABSTRACT Objective: To evaluate the health-related quality of life (HRQoL) of children/adolescents with asthma and that of their caregivers, comparing the two. Methods: This was a systematic review and meta-analysis based on the criteria of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, with a strategy of searching five health-related databases (MEDLINE/PubMed, EMBASE, ScienceDirect, SciELO, and LILACS). We included studies that evaluated the HRQoL of children/adolescents with asthma and that of their caregivers with the Pediatric Asthma Quality of Life Questionnaire and the Pediatric Asthma Caregiver's Quality of Life Questionnaire, respectively, using the total scores and the scores on the domains activity limitation, symptoms (children/adolescents only), and emotional function. Results: We identified 291 articles, and we evaluated 133 of those. A total of 33 articles, collectively including 4,101 subjects, were included in the meta-analysis. An analysis stratified by study design showed no differences between the HRQoL of the caregivers and that of the children/adolescents in the activity limitation domain and in the total score. However, the mean emotional function domain scores were significantly higher (better) among children/adolescents with asthma than among their caregivers in longitudinal studies-Δ = 0.82 (0.21-1.44)-and randomized clinical trials-Δ = 0.52 (0.29-0.79)-although not in cross-sectional studies-Δ = −0.20 (−0.03 to 0.43). Conclusions: The total HRQoL scores proved to be similar between children/adolescents with asthma and their caregivers. However, the two groups differed in their perception of their emotional function, the caregivers scoring significantly lower than the children/adolescents in that domain.


RESUMO Objetivo: Avaliar e comparar os níveis de qualidade de vida relacionada à saúde (QVRS) de crianças/adolescentes com asma e de seus cuidadores. Métodos: Revisão sistemática e meta-análise baseada nos critérios de Preferred Reporting Items for Systematic Reviews and Meta-Analyses, com estratégia de busca em cinco bases de dados em saúde (MEDLINE/PubMed, EMBASE, ScienceDirect, SciELO e LILACS). Foram incluídos estudos que avaliaram a QVRS de crianças/adolescentes com asma e de seus cuidadores por meio dos escores totais e dos domínios limitação de atividades, sintomas (somente crianças/adolescentes) e função emocional do Pediatric Asthma Quality of Life Questionnaire e do Pediatric Asthma Caregiver's Quality of Life Questionnaire, respectivamente. Resultados: Do total de 291 artigos identificados, 133 foram avaliados e 33 foram incluídos na meta-análise, totalizando 4.101 sujeitos. A análise estratificada por tipo de delineamento não mostrou diferenças entre a QVRS de cuidadores e de crianças/adolescentes no domínio limitação de atividades e no escore total. Contudo, houve diferenças das médias no domínio função emocional em estudos longitudinais e ensaios clínicos randomizados - estudos transversais: Δ = −0,20 (−0,03 a 0,43); estudos longitudinais: Δ = 0,82 (0,21-1,44); e ensaios clínicos randomizados: Δ = 0,52 (0,29-0,79) - sendo que os cuidadores apresentaram menores escores que as crianças/adolescentes com asma. Conclusões: Os escores da QVRS entre cuidadores e crianças/adolescentes com asma demonstraram ser semelhantes quanto aos escores totais, mas divergiram na percepção das limitações emocionais, visto que os cuidadores apresentaram escores significativamente menores que as crianças/adolescentes nesse domínio.


Assuntos
Humanos , Criança , Adolescente , Qualidade de Vida , Asma/psicologia , Cuidadores/psicologia , Asma/fisiopatologia , Nível de Saúde , Estudos Transversais
20.
Exp Gerontol ; 46(10): 773-80, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21619925

RESUMO

Reproduction alters the male physiology. We performed a comprehensive examination of oxidative stress in the kidneys of male rats with (experienced) or without (naïve) reproductive activity during aging. Oxidative stress was assessed by measuring the activity of catalase, glutathione peroxidase, glutathione S-transferase, and superoxide dismutase, and by measuring protein carbonylation, lipid peroxidation, nitrite and nitrate levels, vitamin C levels, and glutathione (total, reduced, and oxidized forms) levels, and metabolism was accessed by aconitase activity in kidney tissue, as well as testosterone and estradiol levels in serum. Reproductively active animals exhibited increased testosterone levels and altered metabolism. Aging affects tissues and organs and contributes to their functional decline. Elderly naïve rats showed high nitrite and nitrate levels. The experienced rats had less damage in elderly ages, probably because they had higher antioxidant amount and antioxidant enzyme activities at earlier ages, which would have avoided oxidative damage seen in naïve group, and because of the metabolism decline. Glutathione increase in naïve elder rats probably was induced for direct protection against oxidative damage and indirect protection by higher glutathione peroxidase and glutathione S-transferase activities. Linear regression shows that lipid peroxidation levels explained vitamin C levels (B standardized value of 0.42), indicating that vitamin C was properly produced or recruited into kidneys to combat lipid peroxidation. Catalase activity reflected the protein carbonylation and lipid peroxidation levels (B standardized values of 0.28 and 0.48). These results add comprehensive data regarding changes in oxidative stress during aging, and suggest an explanation for the costs of reproduction.


Assuntos
Envelhecimento/metabolismo , Rim/metabolismo , Estresse Oxidativo , Animais , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Estradiol/sangue , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Rim/enzimologia , Modelos Lineares , Peroxidação de Lipídeos , Masculino , Nitratos/metabolismo , Nitritos/metabolismo , Carbonilação Proteica , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Testosterona/sangue
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