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2.
BMJ Open ; 12(6): e059110, 2022 06 13.
Article in English | MEDLINE | ID: covidwho-1891837

ABSTRACT

OBJECTIVE: This study aimed to propose a simple, accessible and low-cost predictive clinical model to detect lung lesions due to COVID-19 infection. DESIGN: This prospective cohort study included COVID-19 survivors hospitalised between 30 March 2020 and 31 August 2020 followed-up 6 months after hospital discharge. The pulmonary function was assessed using the modified Medical Research Council (mMRC) dyspnoea scale, oximetry (SpO2), spirometry (forced vital capacity (FVC)) and chest X-ray (CXR) during an in-person consultation. Patients with abnormalities in at least one of these parameters underwent chest CT. mMRC scale, SpO2, FVC and CXR findings were used to build a machine learning model for lung lesion detection on CT. SETTING: A tertiary hospital in Sao Paulo, Brazil. PARTICIPANTS: 749 eligible RT-PCR-confirmed SARS-CoV-2-infected patients aged ≥18 years. PRIMARY OUTCOME MEASURE: A predictive clinical model for lung lesion detection on chest CT. RESULTS: There were 470 patients (63%) that had at least one sign of pulmonary involvement and were eligible for CT. Almost half of them (48%) had significant pulmonary abnormalities, including ground-glass opacities, parenchymal bands, reticulation, traction bronchiectasis and architectural distortion. The machine learning model, including the results of 257 patients with complete data on mMRC, SpO2, FVC, CXR and CT, accurately detected pulmonary lesions by the joint data of CXR, mMRC scale, SpO2 and FVC (sensitivity, 0.85±0.08; specificity, 0.70±0.06; F1-score, 0.79±0.06 and area under the curve, 0.80±0.07). CONCLUSION: A predictive clinical model based on CXR, mMRC, oximetry and spirometry data can accurately screen patients with lung lesions after SARS-CoV-2 infection. Given that these examinations are highly accessible and low cost, this protocol can be automated and implemented in different countries for early detection of COVID-19 sequelae.


Subject(s)
COVID-19 , Adolescent , Adult , Brazil/epidemiology , COVID-19/diagnosis , Humans , Lung/diagnostic imaging , Prospective Studies , SARS-CoV-2 , Survivors
3.
J Bras Pneumol ; 48(3): e20210438, 2022.
Article in English, Portuguese | MEDLINE | ID: covidwho-1836602

ABSTRACT

This brief communication demonstrates the correlation of persistent respiratory symptoms with functional, tomographic, and transbronchial pulmonary biopsy findings in patients with COVID-19 who had a long follow-up period. We report a series of six COVID-19 patients with pulmonary involvement who presented with persistent dyspnea within 4-15 months of discharge. We performed transbronchial biopsies, and the histopathological pattern consistently demonstrated peribronchial remodeling with interstitial pulmonary fibrosis. Therefore, lung biopsy may be useful in the approach of patients with long COVID-19, although the type of procedure, its precise indication, and the moment to perform it are yet to be clarified. (Brazilian Registry of Clinical Trials-ReBEC; identifier: RBR-8j9kqy [http://www.ensaiosclinicos.gov.br]).


Subject(s)
COVID-19 , Lung Diseases, Interstitial , Biopsy/methods , COVID-19/complications , Humans , Lung/diagnostic imaging , Lung/pathology , Lung Diseases, Interstitial/pathology
4.
Psychol Med ; : 1-12, 2022 May 06.
Article in English | MEDLINE | ID: covidwho-1829890

ABSTRACT

BACKGROUND: Despite the multitude of clinical manifestations of post-acute sequelae of SARS-CoV-2 infection (PASC), studies applying statistical methods to directly investigate patterns of symptom co-occurrence and their biological correlates are scarce. METHODS: We assessed 30 symptoms pertaining to different organ systems in 749 adults (age = 55 ± 14 years; 47% female) during in-person visits conducted at 6-11 months after hospitalization due to coronavirus disease 2019 (COVID-19), including six psychiatric and cognitive manifestations. Symptom co-occurrence was initially investigated using exploratory factor analysis (EFA), and latent variable modeling was then conducted using Item Response Theory (IRT). We investigated associations of latent variable severity with objective indices of persistent physical disability, pulmonary and kidney dysfunction, and C-reactive protein and D-dimer blood levels, measured at the same follow-up assessment. RESULTS: The EFA extracted one factor, explaining 64.8% of variance; loadings were positive for all symptoms, and above 0.35 for 16 of them. The latent trait generated using IRT placed fatigue, psychiatric, and cognitive manifestations as the most discriminative symptoms (coefficients > 1.5, p < 0.001). Latent trait severity was associated with decreased body weight and poorer physical performance (coefficients > 0.240; p ⩽ 0.003), and elevated blood levels of C-reactive protein (coefficient = 0.378; 95% CI 0.215-0.541; p < 0.001) and D-dimer (coefficient = 0.412; 95% CI 0.123-0.702; p = 0.005). Results were similar after excluding subjects with pro-inflammatory comorbidities. CONCLUSIONS: Different symptoms that persist for several months after moderate or severe COVID-19 may unite within one latent trait of PASC. This trait is dominated by fatigue and psychiatric symptoms, and is associated with objective signs of physical disability and persistent systemic inflammation.

5.
Einstein (Säo Paulo) ; 19: eAO6363, 2021. tab, graf
Article in English | WHO COVID, LILACS (Americas) | ID: covidwho-1614545

ABSTRACT

ABSTRACT Objective To evaluate the role of chest computed tomography in patients with COVID-19 who presented initial negative result in reverse transcriptase-polymerase chain reaction (RT-PCR). Methods A single-center, retrospective study that evaluated 39 patients with negative RT-PCR for COVID-19, who underwent chest computed tomography and had a final clinical or serological diagnosis of COVID-19. The visual tomographic classification was evaluated according to the Consensus of the Radiological Society of North America and software developed with artificial intelligence for automatic detection of findings and chance estimation of COVID-19. Results In the visual tomographic analysis, only one of them (3%) presented computed tomography classified as negative, 69% were classified as typical and 28% as indeterminate. In the evaluation using the software, only four (about 10%) had a probability of COVID-19 <25%. Conclusion Computed tomography can play an important role in management of suspected cases of COVID-19 with initial negative results in RT-PCR, especially considering those patients outside the ideal window for sample collection for RT-PCR.


RESUMO Objetivo Avaliar o papel da tomografia computadorizada de tórax em pacientes com COVID-19 que apresentaram reação em cadeia da polimerase via transcriptase reversa (RT-PCR) inicial falsamente negativa. Métodos Estudo retrospectivo de centro único que avaliou 39 pacientes com RT-PCR negativa para COVID-19, submetidos à tomografia computadorizada de tórax e que tiveram diagnóstico final clínico ou serológico de COVID-19. A classificação tomográfica visual foi avaliada de acordo com o Consenso da Radiological Society of North America e o software desenvolvido com inteligência artificial para detecção automática de achados e estimativa de probabilidade de COVID-19. Resultados Na análise tomográfica visual, somente um deles (3%) apresentou tomografia computadorizada classificada como tendo resultado negativo, 69% foram classificados como típicos e 28% como indeterminados. Na avaliação com uso de software, somente quatro (cerca de 10%) tiveram probabilidade de COVID-19 <25%. Conclusão A tomografia computadorizada pode desempenhar papel importante no manejo de casos suspeitos de COVID-19 com RT-PCR inicialmente negativa, principalmente levando-se em consideração os pacientes que estão fora da janela ideal para coleta de amostra para RT-PCR.


Subject(s)
Humans , COVID-19 , Artificial Intelligence , Tomography, X-Ray Computed , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Lung
7.
Clinics (Sao Paulo) ; 76: e3503, 2021.
Article in English | MEDLINE | ID: covidwho-1561553

ABSTRACT

OBJECTIVE: To investigate the relationship between lung lesion burden (LLB) found on chest computed tomography (CT) and 30-day mortality in hospitalized patients with high clinical suspicion of coronavirus disease 2019 (COVID-19), accounting for tomographic dynamic changes. METHODS: Patients hospitalized with high clinical suspicion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a dedicated and reference hospital for COVID-19, having undergone at least one RT-PCR test, regardless of the result, and with one CT compatible with COVID-19, were retrospectively studied. Clinical and laboratory data upon admission were assessed, and LLB found on CT was semi-quantitatively evaluated through visual analysis. The primary outcome was 30-day mortality after admission. Secondary outcomes, including the intensive care unit (ICU) admission, mechanical ventilation used, and length of stay (LOS), were assessed. RESULTS: A total of 457 patients with a mean age of 57±15 years were included. Among these, 58% presented with positive RT-PCR result for COVID-19. The median time from symptom onset to RT-PCR was 8 days [interquartile range 6-11 days]. An initial LLB of ≥50% using CT was found in 201 patients (44%), which was associated with an increased crude at 30-day mortality (31% vs. 15% in patients with LLB of <50%, p<0.001). An LLB of ≥50% was also associated with an increase in the ICU admission, the need for mechanical ventilation, and a prolonged LOS after adjusting for baseline covariates and accounting for the CT findings as a time-varying covariate; hence, patients with an LLB of ≥50% remained at a higher risk at 30-day mortality (adjusted hazard ratio 2.17, 95% confidence interval 1.47-3.18, p<0.001). CONCLUSION: Even after accounting for dynamic CT changes in patients with both clinical and imaging findings consistent with COVID-19, an LLB of ≥50% might be associated with a higher risk of mortality.


Subject(s)
COVID-19 , Adult , Aged , Humans , Lung/diagnostic imaging , Middle Aged , Prognosis , Retrospective Studies , SARS-CoV-2 , Tomography, X-Ray Computed
8.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-294389

ABSTRACT

Background: COVID-19 patients may have long-term pulmonary consequences. This study developed a simple and accessible screening protocol to detect chronic lung lesions due to COVID-19 infection.Methods: This prospective cohort study included COVID-19 survivors hospitalized between March 30 and August 31, 2020, and re-examined 6 months after admission to the ward or intensive care unit of a tertiary hospital in Sao Paulo, Brazil. Demographic and anthropometric data were collected during interviews, and pulmonary function was assessed using the modified Medical Research Council (mMRC) dyspnoea scale, oximetry (SpO2), spirometry (forced vital capacity [FVC]), and chest X-ray (CXR). Patients with changes in at least one of these examinations were invited to undergo chest computed tomography (CT). The results of the mMRC scale, SpO2, FVC, and CXR were used to train a machine learning model to detect lung lesions on CT.Findings: A total of 749 patients participated in the study. After a general assessment, 470 (63%) presented at least one sign of pulmonary involvement. Among the patients who underwent CT, 48% had significant pulmonary changes, including ground-glass opacities, parenchymal bands, reticulation, traction bronchiectasis, and architectural distortion. The results showed that the machine learning model accurately detected pulmonary lesions (Sensitivity of 0.85±0.08, Specificity of 0.70±0.06, F1-score of 0.79±0.06 and AUC of 0.80±0.07) by the joint analysis of CXR, mMRC scale, SpO2, and FVC data.Interpretation : The joint analysis of CXR, mMRC, SpO2, and spirometry data can accurately screen patients at risk of developing chronic lung lesions after SARS-CoV-2 infection. Given that these examinations are highly accessible and low cost, this protocol can be automated and implemented in different countries.Funding: This study was partially supported by FAPESP (grant 2020/07200- 9) “Analysing Complex Data Linked to COVID-19 to Support Decision Making and Prognosis”Declaration of Interest: None to declare. Ethical Approval: All research procedures were approved by the Research Ethics Committee of ourinstitution (Process No. 31942020.0.000.0068).

9.
J Bras Pneumol ; 47(4): e20210206, 2021 08 11.
Article in English, Portuguese | MEDLINE | ID: covidwho-1362837
10.
BMJ Open ; 11(6): e051706, 2021 06 30.
Article in English | MEDLINE | ID: covidwho-1290077

ABSTRACT

INTRODUCTION: COVID-19 may lead to persistent and potentially incapacitating clinical manifestations (post-acute sequelae of SARS-CoV-2 infection (PASC)). Using easy-to-apply questionnaires and scales (often by telephone interviewing), several studies evaluated samples of COVID-19 inpatients from 4 weeks to several months after discharge. However, studies conducting systematic multidisciplinary assessments of PASC manifestations are scarce, with thorough in-person objective evaluations restricted to modestly sized subsamples presenting greatest disease severity. METHODS AND ANALYSES: We will conduct a prospective observational study of surviving individuals (above 18 years of age) from a cohort of over 3000 subjects with laboratory-confirmed COVID-19 who were treated as inpatients at the largest academic health centre in Sao Paulo, Brazil (Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo). All eligible subjects will be consecutively invited to undergo a 1-2-day series of multidisciplinary assessments at 2 time-points, respectively, at 6-9 months and 12-15 months after discharge. Assessment schedules will include detailed multidomain questionnaires applied by medical research staff, self-report scales, objective evaluations of cardiopulmonary functioning, physical functionality and olfactory status, standardised neurological, psychiatric and cognitive examinations, as well as diagnostic laboratory, muscle ultrasound and chest imaging exams. Remaining material from blood tests will be incorporated by a local biobank for use in future investigations on inflammatory markers, genomics, transcriptomics, peptidomics and metabolomics. ETHICS AND DISSEMINATION: All components of this programme have been approved by local research ethics committees. We aim to provide insights into the frequency and severity of chronic/post-COVID multiorgan symptoms, as well as their interrelationships and associations with acute disease features, sociodemographic variables and environmental exposures. Findings will be disseminated in peer-reviewed journals and at scientific meetings. Additionally, we aim to provide a data repository to allow future pathophysiological investigations relating clinical PASC features to biomarker data extracted from blood samples. TRIAL REGISTRATION NUMBER: RBR-8z7v5wc; Pre-results.


Subject(s)
COVID-19 , SARS-CoV-2 , Brazil , COVID-19/complications , Hospitalization , Humans , Observational Studies as Topic
11.
Expert Rev Respir Med ; 15(6): 791-803, 2021 06.
Article in English | MEDLINE | ID: covidwho-1203511

ABSTRACT

Introduction: Coronavirus disease 2019 (COVID-19) is still increasing worldwide, and as a result, the number of patients with pulmonary fibrosis secondary to COVID-19 will expand over time. Risk factors, histopathological characterization, pathophysiology, prevalence, and management of post-COVID-19 pulmonary fibrosis are poorly understood, and few studies have addressed these issues.Areas covered:This article reviews the current evidence regarding post-COVID-19 pulmonary fibrosis, with an emphasis on the potential risk factors, histopathology, pathophysiology, functional and tomographic features, and potential therapeutic modalities. A search on the issue was performed in the MEDLINE, Embase, and SciELO databases and the Cochrane library between 1 December 2019, and 25 January 2021. Studies were reviewed and relevant topics were incorporated into this narrative review. Expert opinion: Pulmonary sequelae may occur secondary to COVID-19, which needs to be included as a potential etiology in the current differential diagnosis of pulmonary fibrosis. Therefore, serial clinical, tomographic, and functional screening for pulmonary fibrosis is recommended after COVID-19, mainly in patients with pulmonary involvement in the acute phase of the disease. Further studies are necessary to determine the risk factors, markers, pathophysiology, and appropriate management of post-COVID-19 pulmonary fibrosis.


Subject(s)
COVID-19/complications , Pulmonary Fibrosis/etiology , COVID-19/diagnosis , COVID-19/pathology , COVID-19/therapy , Databases, Factual , Diagnosis, Differential , Disease Progression , Humans , Lung/pathology , Lung/virology , Pulmonary Fibrosis/diagnosis , Pulmonary Fibrosis/pathology , Pulmonary Fibrosis/therapy , Risk Factors , SARS-CoV-2/physiology , Severity of Illness Index , Tomography, X-Ray Computed/methods
12.
Clinics ; 76: e2476, 2021. tab, graf
Article in English | WHO COVID, LILACS (Americas) | ID: covidwho-1159502

ABSTRACT

OBJECTIVE: To determine the correlation between the two tomographic classifications for coronavirus disease (COVID-19), COVID-19 Reporting and Data System (CORADS) and Radiological Society of North America Expert Consensus Statement on Reporting Chest Computed Tomography (CT) Findings Related to COVID-19 (RSNA), in the Brazilian population and to assess the agreement between reviewers with different experience levels. METHODS: Chest CT images of patients with reverse transcriptase-polymerase chain reaction (RT-PCR)-positive COVID-19 were categorized according to the CORADS and RSNA classifications by radiologists with different levels of experience and who were initially unaware of the RT-PCR results. The inter- and intra-observer concordances for each of the classifications were calculated, as were the concordances between classifications. RESULTS: A total of 100 patients were included in this study. The RSNA classification showed an almost perfect inter-observer agreement between reviewers with similar experience levels, with a kappa coefficient of 0.892 (95% confidence interval [CI], 0.788-0.995). CORADS showed substantial agreement among reviewers with similar experience levels, with a kappa coefficient of 0.642 (95% CI, 0.491-0.793). There was inter-observer variation when comparing less experienced reviewers with more experienced reviewers, with the highest kappa coefficient of 0.396 (95% CI, 0.255-0.588). There was a significant correlation between both classifications, with a Kendall coefficient of 0.899 (p<0.001) and substantial intra-observer agreement for both classifications. CONCLUSION: The RSNA and CORADS classifications showed excellent inter-observer agreement for reviewers with the same level of experience, although the agreement between less experience reviewers and the reviewer with the most experience was only reasonable. Combined analysis of both classifications with the first RT-PCR results did not reveal any false-negative results for detecting COVID-19 in patients.


Subject(s)
Humans , Coronavirus Infections , Coronavirus , Brazil , Tomography, X-Ray Computed , Observer Variation , Betacoronavirus
13.
Radiol. bras ; 53(6):397-400, 2020.
Article in English | LILACS (Americas), Grey literature | ID: grc-742382

ABSTRACT

The objective of this article is to share the strategy we used in order to restructure the radiology and diagnostic imaging department of a referral institution during the coronavirus disease 2019 pandemic, on the basis of the current recommendations. It is essential to integrate the work of supervisors, preceptors, and residents, maintaining communication and sharing decisions, with mutual support, as well as to determine the best strategy to be adopted in this scenario of uncertainty and constant change, while also ensuring adequate emotional support for all parties. Resumo O objetivo deste artigo é compartilhar a estratégia de como estruturamos o departamento de radiologia e diagnóstico por imagem de uma instituição de referência na pandemia da COVID-19, baseados nas recomendações vigentes. É fundamental a integração entre supervisores, preceptores e residentes, sempre mantendo comunicação e compartilhamento das decisões, com apoio mútuo, decidindo a melhor estratégia a ser seguida neste cenário de incertezas e de mudanças contínuas, garantindo ainda suporte emocional adequado a todos.

15.
Radiol. bras ; 53(4):255-261, 2020.
Article in English | LILACS (Americas), Grey literature | ID: grc-742337

ABSTRACT

China was the epicenter for the novel coronavirus disease (COVID-19), which quickly spread to other Asian countries and later to Western countries;subsequently, COVID-19 was categorized as a pandemic by the World Health Organization. Diagnosis primarily depends on viral detection in respiratory samples;however, available kits are limited, lack high sensitivity, and have a long turnaround time for providing results. In this scenario, computed tomography has emerged as an efficient and available high-sensitivity method, allowing radiologists to readily recognize findings related to COVID-19. The objective of this article is to demonstrate the main tomographic findings in symptomatic respiratory patients with COVID-19 to assist medical professionals during this critical moment. Resumo A doença pelo novo coronavírus (COVID-19) teve epicentro na China e rapidamente se espalhou pelos demais países asiáticos e, posteriormente, para os países ocidentais, sendo definida como pandemia pela Organização Mundial da Saúde. O diagnóstico da COVID-19 é primariamente dependente da pesquisa do vírus nas vias aéreas superiores, mas os kits para sua confirmação ainda são limitados, não apresentam sensibilidade elevada e os resultados são demorados. Nesse cenário, a tomografia computadorizada surge como método eficiente e disponível e com alta sensibilidade, cabendo a nós radiologistas reconhecer prontamente os achados relacionados a essa doença. O objetivo deste artigo é demonstrar os principais achados tomográficos de tórax em pacientes sintomáticos respiratórios infectados pela COVID-19, de modo a auxiliar os colegas nesse momento crítico.

16.
Clinics ; 75:e2027-e2027, 2020.
Article in English | LILACS (Americas), Grey literature | ID: grc-742336

ABSTRACT

The coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in Wuhan city and was declared a pandemic in March 2020. Although the virus is not restricted to the lung parenchyma, the use of chest imaging in COVID-19 can be especially useful for patients with moderate to severe symptoms or comorbidities. This article aimed to demonstrate the chest imaging findings of COVID-19 on different modalities: chest radiography, computed tomography, and ultrasonography. In addition, it intended to review recommendations on imaging assessment of COVID-19 and to discuss the use of a structured chest computed tomography report. Chest radiography, despite being a low-cost and easily available method, has low sensitivity for screening patients. It can be useful in monitoring hospitalized patients, especially for the evaluation of complications such as pneumothorax and pleural effusion. Chest computed tomography, despite being highly sensitive, has a low specificity, and hence cannot replace the reference diagnostic test (reverse transcription polymerase chain reaction). To facilitate the confection and reduce the variability of radiological reports, some standardizations with structured reports have been proposed. Among the available classifications, it is possible to divide the radiological findings into typical, indeterminate, atypical, and negative findings. The structured report can also contain an estimate of the extent of lung involvement (e.g., more or less than 50% of the lung parenchyma). Pulmonary ultrasonography can also be an auxiliary method, especially for monitoring hospitalized patients in intensive care units, where transfer to a tomography scanner is difficult.

18.
Radiol Bras ; 53(6): 397-400, 2020.
Article in English | MEDLINE | ID: covidwho-945431

ABSTRACT

The objective of this article is to share the strategy we used in order to restructure the radiology and diagnostic imaging department of a referral institution during the coronavirus disease 2019 pandemic, on the basis of the current recommendations. It is essential to integrate the work of supervisors, preceptors, and residents, maintaining communication and sharing decisions, with mutual support, as well as to determine the best strategy to be adopted in this scenario of uncertainty and constant change, while also ensuring adequate emotional support for all parties.


O objetivo deste artigo é compartilhar a estratégia de como estruturamos o departamento de radiologia e diagnóstico por imagem de uma instituição de referência na pandemia da COVID-19, baseados nas recomendações vigentes. É fundamental a integração entre supervisores, preceptores e residentes, sempre mantendo comunicação e compartilhamento das decisões, com apoio mútuo, decidindo a melhor estratégia a ser seguida neste cenário de incertezas e de mudanças contínuas, garantindo ainda suporte emocional adequado a todos.

20.
Radiol Bras ; 53(4): 255-261, 2020.
Article in English | MEDLINE | ID: covidwho-750954

ABSTRACT

China was the epicenter for the novel coronavirus disease (COVID-19), which quickly spread to other Asian countries and later to Western countries; subsequently, COVID-19 was categorized as a pandemic by the World Health Organization. Diagnosis primarily depends on viral detection in respiratory samples; however, available kits are limited, lack high sensitivity, and have a long turnaround time for providing results. In this scenario, computed tomography has emerged as an efficient and available high-sensitivity method, allowing radiologists to readily recognize findings related to COVID-19. The objective of this article is to demonstrate the main tomographic findings in symptomatic respiratory patients with COVID-19 to assist medical professionals during this critical moment.


A doença pelo novo coronavírus (COVID-19) teve epicentro na China e rapidamente se espalhou pelos demais países asiáticos e, posteriormente, para os países ocidentais, sendo definida como pandemia pela Organização Mundial da Saúde. O diagnóstico da COVID-19 é primariamente dependente da pesquisa do vírus nas vias aéreas superiores, mas os kits para sua confirmação ainda são limitados, não apresentam sensibilidade elevada e os resultados são demorados. Nesse cenário, a tomografia computadorizada surge como método eficiente e disponível e com alta sensibilidade, cabendo a nós radiologistas reconhecer prontamente os achados relacionados a essa doença. O objetivo deste artigo é demonstrar os principais achados tomográficos de tórax em pacientes sintomáticos respiratórios infectados pela COVID-19, de modo a auxiliar os colegas nesse momento crítico.

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