Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22269768

RESUMO

The release of neutrophil extracellular traps (NETs) is associated with inflammation, coagulopathy, and organ damage found in severe cases of COVID-19. However, the molecular mechanisms underlying the release of NETs in COVID-19 remain unclear. Using a single-cell transcriptome analysis we observed that the expression of GSDMD and inflammasome-related genes were increased in neutrophils from COVID-19 patients. Furthermore, high expression of GSDMD was found associated with NETs structures in the lung tissue of COVID-19 patients. The activation of GSDMD in neutrophils requires live SARS-CoV-2 and occurs after neutrophil infection via ACE2 receptors and serine protease TMPRSS2. In a mouse model of SARS-CoV-2 infection, the treatment with GSDMD inhibitor (disulfiram) reduced NETs release and organ damage. These results demonstrated that GSDMD-dependent NETosis plays a critical role in COVID-19 immunopathology, and suggests that GSDMD inhibitors, can be useful to COVID-19 treatment. In BriefHere, we showed that the activation of the Gasdermin-D (GSDMD) pathway in neutrophils controls NET release during COVID-19. The inhibition of GSDMD with disulfiram, abrogated NET formation reducing lung inflammation and tissue damage. These findings suggest GSDMD as a target for improving the COVID-19 therapy.

2.
Fernanda Crunfli; Victor Corasolla Carregari; Flavio Protasio Veras; Pedro Henrique Vendramini; Aline Gazzola Fragnani Valenca; Andre Saraiva Leao Marcelo Antunes; Carolina Brandao-Teles; Giuliana da Silva Zuccoli; Guilherme Reis-de-Oliveira; Licia C. Silva-Costa; Verônica Monteiro Saia-Cereda; Bradley Joseph Smith; Ana Campos Codo; Gabriela Fabiano de Souza; Stéfanie Primon Muraro; Pierina Lorencini Parise; Daniel A. Toledo-Teixeira; Icaro Maia Santos de Castro; Bruno Marcel Silva Melo; Glaucia M. Almeida; Egidi Mayara Silva Firmino; Isadora Marques Paiva; Bruna Manuella Souza Silva; Rafaela Mano Guimaraes; Niele D. Mendes; Raíssa Guimarães Ludwig; Gabriel Palermo Ruiz; Thiago Leite Knittel; Gustavo Gastão Davanzo; Jaqueline Aline Gerhardt; Patrícia Brito Rodrigues; Julia Forato; Mariene Ribeiro Amorim; Natália Brunetti Silva; Matheus Cavalheiro Martini; Maíra Nilson Benatti; Sabrina Batah; Li Siyuan; Rafael Batista João; Lucas Scardua Silva; Mateus Henrique Nogueira; ítalo Karmann Aventurato; Mariana Rabelo de Brito; Marina Koutsodontis Machado Alvim; José Roberto da Silva Junior; Lívia Liviane Damião; Maria Ercilia de Paula Castilho Stefano; Iêda Maria Pereira de Sousa; Elessandra Dias da Rocha; Solange Maria Gonçalves; Luiz Henrique Lopes da Silva; Vanessa Bettini; Brunno Machado de Campos; Guilherme Ludwig; Lucas Alves Tavares; Marjorie Cornejo Pontelli; Rosa Maria Mendes Viana; Ronaldo Martins; Andre S. Vieira; José Carlos Alves-Filho; Eurico de Arruda Neto; Guilherme Podolski-Gondim; Marcelo Volpon Santos; Luciano Neder; Fernando Cendes; Paulo Louzada-Junior; Rene Donizeti Oliveira; Fernando Q Cunha Sr.; André Damásio; Marco Aurélio Ramirez Vinolo; Carolina Demarchi Munhoz; Stevens K Rehen Sr.; Helder I Nakaya; Thais Mauad; Amaro Nunes Duarte-Neto; Luiz Fernando Ferraz da Silva; Marisa Dolhnikoff; Paulo Saldiva; Alessandro S Farias; Pedro Manoel M. Moraes-Vieira; Alexandre Todorovic Fabro; Adriano Sebollela; José Luiz Proença Módena; Clarissa Lin Yasuda; Marcelo A. Mori; Thiago Mattar Cunha; Daniel Martins-de-Souza.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20207464

RESUMO

Although increasing evidence confirms neuropsychiatric manifestations associated mainly with severe COVID-19 infection, the long-term neuropsychiatric dysfunction has been frequently observed after mild infection. Here we show the spectrum of the cerebral impact of SARS-CoV-2 infection ranging from long-term alterations in mildly infected individuals (orbitofrontal cortical atrophy, neurocognitive impairment, excessive fatigue and anxiety symptoms) to severe acute damage confirmed in brain tissue samples extracted from the orbitofrontal region (via endonasal trans-ethmoidal approach) from individuals who died of COVID-19. We used surface-based analyses of 3T MRI and identified orbitofrontal cortical atrophy in a group of 81 mildly infected patients (77% referred anosmia or dysgeusia during acute stage) compared to 145 healthy volunteers; this atrophy correlated with symptoms of anxiety and cognitive dysfunction. In an independent cohort of 26 individuals who died of COVID-19, we used histopathological signs of brain damage as a guide for possible SARS-CoV-2 brain infection, and found that among the 5 individuals who exhibited those signs, all of them had genetic material of the virus in the brain. Brain tissue samples from these 5 patients also exhibited foci of SARS-CoV-2 infection and replication, particularly in astrocytes. Supporting the hypothesis of astrocyte infection, neural stem cell-derived human astrocytes in vitro are susceptible to SARS-CoV-2 infection through a non-canonical mechanism that involves spike-NRP1 interaction. SARS-CoV-2-infected astrocytes manifested changes in energy metabolism and in key proteins and metabolites used to fuel neurons, as well as in the biogenesis of neurotransmitters. Moreover, human astrocyte infection elicits a secretory phenotype that reduces neuronal viability. Our data support the model in which SARS-CoV-2 reaches the brain, infects astrocytes and consequently leads to neuronal death or dysfunction. These deregulated processes are also likely to contribute to the structural and functional alterations seen in the brains of COVID-19 patients.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20169573

RESUMO

IntroductionNeutrophilia and high levels of proinflammatory cytokines and other mediators of inflammation are common finds in patients with severe acute respiratory syndrome due to COVID-19. By its action on leukocytes, we propose colchicine as an intervention worthy of being tested. ObjectiveTo evaluate whether the addition of colchicine to standard treatment for COVID-19 results in better outcomes. MethodsWe present the interim analysis of a single-center randomized, double-blinded, placebo controlled clinical trial of colchicine for the treatment of moderate to severe COVID-19, with 38 patients allocated 1:1 from April 11 to July 06, 2020. Colchicine regimen was 0.5 mg thrice daily for 5 days, then 0.5 mg twice daily for 5 days. The first dose was 1.0 mg whether body weight was [≥] 80 kg. EndpointsThe primary endpoints were the need for supplemental oxygen; time of hospitalization; need for admission and length of stay in intensive care units; and death rate and causes of mortality. As secondary endpoints, we assessed: serum C-reactive protein, serum Lactate dehydrogenase and relation neutrophil to lymphocyte of peripheral blood samples from day zero to day 7; the number, type, and severity of adverse events; frequency of interruption of the study protocol due to adverse events; and frequency of QT interval above 450 ms. ResultsThirty-five patients (18 for Placebo and 17 for Colchicine) completed the study. Both groups were comparable in terms of demographic, clinical and laboratory data at baseline. Median (and interquartile range) time of need for supplemental oxygen was 3.0 (1.5-6.5) days for the Colchicine group and 7.0 (3.0-8.5) days for Placebo group (p = 0.02). Median (IQR) time of hospitalization was 6.0 (4.0-8.5) days for the Colchicine group and 8.5 (5.5-11.0) days for Placebo group (p = 0.03). At day 2, 53% vs 83% of patients maintained the need for supplemental oxygen, while at day 7 the values were 6% vs 39%, in the Colchicine and Placebo groups, respectively (log rank; p = 0.01). Hospitalization was maintained for 53% vs 78% of patients at day 5 and 6% vs 17% at day 10, for the Colchicine and Placebo groups, respectively (log rank; p = 0.01). One patient per group needed admission to ICU. No recruited patient died. At day 4, patients of Colchicine group presented significant reduction of serum C-reactive protein compared to baseline (p < 0.001). The majority of adverse events were mild and did not lead to patient withdrawal. Diarrhea was more frequent in the Colchicine group (p = 0.17). Cardiac adverse events were absent. DiscussionThe use of colchicine reduced the length of supplemental oxygen therapy and the length of hospitalization. Clinical improvement was in parallel with a reduction on serum levels of C-reactive protein. The drug was safe and well tolerated. Colchicine may be considered a beneficial and not expensive option for COVID-19 treatment. Clinical trials with larger numbers of patients should be conducted to further evaluate the efficacy and safety of colchicine as an adjunctive therapy for hospitalized patients with moderate to severe COVID-19.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20170043

RESUMO

IntroductionThe progression and severity of the coronavirus disease 2019 (COVID-19), an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), varies significantly in the population. While the hallmarks of SARS-CoV-2 and severe COVID-19 within routine laboratory parameters are emerging, little is known about the impact of sex and age on these profiles. MethodsWe performed multidimensional analysis of millions of records of laboratory parameters and diagnostic tests for 178,887 individuals, of which 33,266 tested positive for SARS-CoV-2. These included complete blood cell count, electrolytes, metabolites, arterial blood gases, enzymes, hormones, cancer biomarkers, and others. ResultsCOVID-19 induced similar alterations in the laboratory parameters in males compared to females. Biomarkers of inflammation, such as C-reactive protein (CRP) and ferritin, were increased especially in older men with COVID-19, whereas other markers such as abnormal liver function tests were common across several age groups, except for young women. Low peripheral blood basophils and eosinophils were also more common in the elderly with COVID-19. Both male and female COVID-19 patients admitted to the intensive care unit (ICU) displayed alterations in the coagulation system, and higher levels of neutrophils, CRP, lactate dehydrogenase (LDH), among others. DiscussionOur study uncovers the laboratory profile of a large cohort of COVID-19 patients that underly discrepancies influenced by aging and biological sex. These profiles directly link COVID-19 disease presentation to an intricate interplay between sex, age and the immune response. One Sentence SummaryBig Data analysis of laboratory results from a large number of COVID-19 patients and controls reveals distinct disease profiles influenced by age and sex which may underly occurrence of severe disease. Key messagesO_ST_ABS- What is the key question?C_ST_ABSLittle is known about the impact of sex and age on the routine laboratory parameters measured in COVID-19 patients. - What is the bottom line?Our in-depth analysis unraveled distinct disease profiles influenced by age and sex which may underly occurrence of severe disease. - Why read on?This work will help physicians to interpret the disease presentation in COIVD-19 patients according to their age and sex.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA