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1.
Antiviral Res ; 229: 105968, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004311

RESUMO

Since human angiotensin-converting enzyme 2 (ACE2) serves as a primary receptor for SARS-CoV-2, characterizing ACE2 regions that allow SARS-CoV-2 to enter human cells is essential for designing peptide-based antiviral blockers and elucidating the pathogenesis of the virus. We identified and synthesized a 25-mer mimetic peptide (encompassing positions 22-46 of the ACE2 alpha-helix α1) implicated in the S1 receptor-binding domain (RBD)-ACE2 interface. The mimetic (wild-type, WT) ACE2 peptide significantly inhibited SARS-CoV-2 infection of human pulmonary Calu-3 cells in vitro. In silico protein modeling predicted that residues F28, K31, F32, F40, and Y41 of the ACE2 alpha-helix α1 are critical for the original, Delta, and Omicron strains of SARS-CoV-2 to establish the Spike RBD-ACE2 interface. Substituting these residues with alanine (A) or aspartic acid (D) abrogated the antiviral protective effect of the peptides, indicating that these positions are critical for viral entry into pulmonary cells. WT ACE2 peptide, but not the A or D mutated peptides, exhibited significant interaction with the SARS-CoV-2 S1 RBD, as shown through molecular dynamics simulations. Through identifying the critical amino acid residues of the ACE2 alpha-helix α1, which is necessary for the Spike RBD-ACE2 interface and mobilized during the in vitro viral infection of cells, we demonstrated that the WT ACE2 peptide protects susceptible K18-hACE2 mice against in vivo SARS-CoV-2 infection and is effective for the treatment of COVID-19.

2.
J Biol Chem ; 300(3): 105700, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307383

RESUMO

Selective retrograde transport from endosomes back to the trans-Golgi network (TGN) is important for maintaining protein homeostasis, recycling receptors, and returning molecules that were transported to the wrong compartments. Two important transmembrane proteins directed to this pathway are the Cation-Independent Mannose-6-phosphate receptor (CI-MPR) and the ATP7B copper transporter. Among CI-MPR functions is the delivery of acid hydrolases to lysosomes, while ATP7B facilitates the transport of cytosolic copper ions into organelles or the extracellular space. Precise subcellular localization of CI-MPR and ATP7B is essential for the proper functioning of these proteins. This study shows that both CI-MPR and ATP7B interact with a variant of the clathrin adaptor 1 (AP-1) complex that contains a specific isoform of the γ-adaptin subunit called γ2. Through synchronized anterograde trafficking and cell-surface uptake assays, we demonstrated that AP-1γ2 is dispensable for ATP7B and CI-MPR exit from the TGN while being critically required for ATP7B and CI-MPR retrieval from endosomes to the TGN. Moreover, AP-1γ2 depletion leads to the retention of endocytosed CI-MPR in endosomes enriched in retromer complex subunits. These data underscore the importance of AP-1γ2 as a key component in the sorting and trafficking machinery of CI-MPR and ATP7B, highlighting its essential role in the transport of proteins from endosomes.


Assuntos
Complexo 1 de Proteínas Adaptadoras , ATPases Transportadoras de Cobre , Endossomos , Transporte Proteico , Receptor IGF Tipo 2 , Rede trans-Golgi , Humanos , Endossomos/metabolismo , Células HeLa , Transporte Proteico/genética , Receptor IGF Tipo 2/genética , Receptor IGF Tipo 2/metabolismo , Rede trans-Golgi/genética , Rede trans-Golgi/metabolismo , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Complexo 1 de Proteínas Adaptadoras/genética , Complexo 1 de Proteínas Adaptadoras/metabolismo , Subunidades gama do Complexo de Proteínas Adaptadoras/metabolismo
3.
An Bras Dermatol ; 99(2): 259-268, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38007314

RESUMO

In dermatologists' clinical practice, the use of systemic glucocorticoids is recurrent for the management of different comorbidities that require chronic immunosuppression. The prescription of this medication requires caution and basic clinical knowledge due to the several adverse effects inherent to the treatment. However, different doubts may arise or inappropriate conduct may be adopted due to the lack of objective and specific guidelines for the screening, prophylaxis and management of complications from chronic corticosteroid therapy. Considering this problem, the authors carried out a narrative review of the literature to gather up-to-date data on adverse effects secondary to the chronic use of systemic glucocorticoids. The broad approach to this topic made it possible to review the pathophysiology and risk factors for these complications, as well as to develop updated orientation that can be used as a learning tool and quick reference for dermatologists during their clinical practice with glucocorticoids.


Assuntos
Dermatologistas , Glucocorticoides , Humanos , Glucocorticoides/efeitos adversos , Fatores de Risco
4.
An. bras. dermatol ; 99(2): 259-268, Mar.-Apr. 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1556830

RESUMO

Abstract In dermatologists' clinical practice, the use of systemic glucocorticoids is recurrent for the management of different comorbidities that require chronic immunosuppression. The prescription of this medication requires caution and basic clinical knowledge due to the several adverse effects inherent to the treatment. However, different doubts may arise or inappropriate conduct may be adopted due to the lack of objective and specific guidelines for the screening, prophylaxis and management of complications from chronic corticosteroid therapy. Considering this problem, the authors carried out a narrative review of the literature to gather up-to-date data on adverse effects secondary to the chronic use of systemic glucocorticoids. The broad approach to this topic made it possible to review the pathophysiology and risk factors for these complications, as well as to develop updated orientation that can be used as a learning tool and quick reference for dermatologists during their clinical practice with glucocorticoids.

5.
Mol Cell Proteomics ; 22(12): 100676, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37940003

RESUMO

Extracellular vesicles (EVs) are biomolecule carriers for intercellular communication in health and disease. Nef is a HIV virulence factor that is released from cells within EVs and is present in plasma EVs of HIV-1 infected individuals. We performed a quantitative proteomic analysis to fully characterize the Nef-induced changes in protein composition of T cell-derived EVs and identify novel host targets of HIV. Several proteins with well-described roles in infection or not previously associated with HIV pathogenesis were specifically modulated by Nef in EVs. Among the downregulated proteins are the interferon-induced transmembrane 1, 2, and 3 (IFITM1-3) proteins, broad-spectrum antiviral factors known to be cell-to-cell transferable by EVs. We demonstrate that Nef depletes IFITM1-3 from EVs by excluding these proteins from the plasma membrane and lipid rafts, which are sites of EVs biogenesis in T cells. Our data establish Nef as a modulator of EVs' global protein content and as an HIV factor that antagonizes IFITMs.


Assuntos
Vesículas Extracelulares , Infecções por HIV , HIV-1 , Humanos , Linfócitos T , Proteoma/metabolismo , Proteômica , Vesículas Extracelulares/metabolismo , Interferons/metabolismo , Infecções por HIV/metabolismo , Antivirais/metabolismo
6.
iScience ; 26(11): 108134, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37867943

RESUMO

AIM2 is an interferon-inducible HIN-200 protein family member and is well-documented for its roles in innate immune responses as a DNA sensor. Recent studies have highlighted AIM2's function on regulatory T cells (Treg) and follicular T cells (Tfh). However, its involvement in Th17 cell differentiation remains unclear. This study reveals that AIM2 promotes Th17 cell differentiation. AIM2 deficiency decreases IL-17A production and downregulates key Th17 associated proteins (RORγt, IL-1R1, IL-23R). AIM2 is located in the nucleus of Th17 cells, where it interacts with RORγt, enhancing its binding to the Il17a promoter. The absence of AIM2 hinders naive CD4 T cells from differentiating into functional Th17 cells and from inducing colitis in Rag1-/- mice. This study uncovers AIM2's role as a regulator of Th17 cell transcriptional programming, highlighting its potential as a therapeutic target for Th17 cell-mediated inflammatory diseases.

7.
Elife ; 122023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37523305

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here, we show that SARS-CoV-2 infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS- CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Linfócitos T CD8-Positivos , Linfócitos T Auxiliares-Indutores , Pulmão
8.
Rev. bras. med. esporte ; 29: e2021_0005, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1387930

RESUMO

ABSTRACT Introduction: The objective of this study was to present a systematic review and meta-analysis to compare total excess post-exercise oxygen consumption (EPOC) for two training intervention models in healthy individuals, and the secondary objective was to understand whether oxygen consumption after exercise could really promote a meaningful help. Design: To design a meta-analysis review to compare two training intervention models (experimental: high-intensity interval training; and control: continuous moderate-intensity) and their effects on total EPOC in healthy individuals. Participants: Seventeen studies were considered to be of good methodological quality and with a low risk of bias. Methods: Literature searches were performed using the electronic databases with no restriction on year of publication. The keywords used were obtained by consulting Mesh Terms (PubMed) and DeCS (BIREME Health Science Descriptors). Results: The present study findings showed a tendency (random-effects model: 0.87, 95%-CI [0.35,1.38], I2=73%, p<0.01) to increase EPOC when measured following high-intensity interval training. Conclusions: Our study focused on the analysis of high- and moderate-intensity oxygen uptake results following exercise. Despite the growing popularity of high-intensity interval training, we found that the acute and chronic benefits remain limited. We understand that the lack of a standard protocol and standard training variables provides limited consensus to determine the magnitude of the EPOC. We suggest that longitudinal experimental studies may provide more robust conclusions. Another confounding factor in the studies investigated was the magnitude (time in minutes) of VO2 measurements when assessing EPOC. Measurement times ranged from 60 min to 720 min. Longitudinal studies and controlled experimental designs would facilitate more precise measurements and correct subject numbers would provide accurate effect sizes. Systematic reviewb of Level II studies.


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RESUMO Introdução: O objetivo deste estudo foi apresentar uma revisão sistemática e metanálise para comparar os efeitos de dois modelos de intervenção de treinamento sobre o consumo excessivo de oxigênio pós-exercício (EPOC) em indivíduos saudáveis em treinamento, e o objetivo secundário foi entender se o consumo de oxigênio depois de exercício realmente pode proporcionar ajuda substancial. Objetivo: Elaborar uma revisão de metanálise para comparar um modelo de treinamento de duas intervenções (experimental: treinamento intervalado de alta intensidade, e controle: contínuo de intensidade moderada) e o efeito sobre o EPOC total em indivíduos saudáveis. Participantes: Os 17 estudos foram considerados de boa qualidade metodológica e baixo risco de viés. Métodos: As buscas bibliográficas foram realizadas nos bancos de dados eletrônicos sem restrição de ano de publicação. Os descritores usados foram obtidos em MeSH (PubMed) e DeCS (Descritores em Ciências da Saúde da BIREME). Resultados: Os achados do presente estudo mostraram uma tendência (modelo de efeitos aleatórios: 0,87, IC 95% [0,35;1,38], I ² = 73%, p < 0,01) de aumento do EPOC quando as medidas foram realizadas depois de treinamento intervalado de alta intensidade. Conclusões: Nosso estudo concentrou-se na análise dos resultados de alta e moderada intensidade no consumo de oxigênio depois do exercício. Apesar da crescente popularidade do treinamento intervalado de alta intensidade, descobrimos que os benefícios agudos e crônicos permanecem limitados. Entendemos que a falta de um protocolo e variáveis padronizadas de treinamento fornecem consenso limitado para determinar a magnitude do EPOC. Sugerimos que estudos experimentais longitudinais podem fornecer conclusões mais robustas. Outro fator de confusão nos estudos investigados foi a magnitude (tempo em minutos) das medidas do VO2na avaliação do EPOC. Os tempos de medição variaram de 60 a 720 min. Estudos longitudinais e projetos experimentais controlados facilitariam medições mais precisas e números corretos de indivíduos forneceriam tamanhos de efeito precisos. Nível de evidência II; Revisão sistemáticabde Estudos.

9.
Cell Rep ; 41(13): 111897, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36577385

RESUMO

Psoriasis is an inflammatory skin disease characterized by keratinocyte proliferation and inflammatory cell infiltration induced by IL-17. However, the molecular mechanism through which IL-17 signaling in keratinocytes triggers skin inflammation remains not fully understood. Pyruvate kinase M2 (PKM2), a glycolytic enzyme, has been shown to have non-metabolic functions. Here, we report that PKM2 mediates IL-17A signaling in keratinocytes triggering skin psoriatic inflammation. We find high expression of PKM2 in the epidermis of psoriatic patients and mice undergoing psoriasis models. Specific depletion of PKM2 in keratinocytes attenuates the development of experimental psoriasis by reducing the production of pro-inflammatory mediators. Mechanistically, PKM2 forms a complex with Act1 and TRAF6 regulating NF-κB transcriptional signaling downstream of the IL-17 receptor. As IL-17 also induces PKM2 expression in keratinocytes, our findings reveal a sustained signaling circuit critical for the psoriasis-driving effects of IL-17A, suggesting that PKM2 is a potential therapeutic target for psoriasis.


Assuntos
Dermatite , Psoríase , Camundongos , Animais , Interleucina-17/metabolismo , Piruvato Quinase/metabolismo , Queratinócitos/metabolismo , Psoríase/induzido quimicamente , Inflamação/metabolismo , Pele/metabolismo
10.
J Biol Chem ; 298(8): 102172, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35753347

RESUMO

One of the hallmarks of Alzheimer's disease is the accumulation of toxic amyloid-ß (Aß) peptides in extracellular plaques. The direct precursor of Aß is the carboxyl-terminal fragment ß (or C99) of the amyloid precursor protein (APP). C99 is detected at elevated levels in Alzheimer's disease brains, and its intracellular accumulation has been linked to early neurotoxicity independently of Aß. Despite this, the causes of increased C99 levels are poorly understood. Here, we demonstrate that APP interacts with the clathrin vesicle adaptor AP-1 (adaptor protein 1), and we map the interaction sites on both proteins. Using quantitative kinetic trafficking assays, established cell lines and primary neurons, we also show that this interaction is required for the transport of APP from the trans-Golgi network to endosomes. In addition, disrupting AP-1-mediated transport of APP alters APP processing and degradation, ultimately leading to increased C99 production and Aß release. Our results indicate that AP-1 regulates the subcellular distribution of APP, altering its processing into neurotoxic fragments.


Assuntos
Doença de Alzheimer , Amiloidose , Complexo de Golgi , Síndromes Neurotóxicas , Proteínas Adaptadoras de Transporte Vesicular , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Complexo de Golgi/metabolismo , Humanos , Fator de Transcrição AP-1/genética
11.
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1362872

RESUMO

Objetivo: Analisar a distribuição espacial das Práticas Integrativas e Complementares em Saúde (PICS) na Atenção Básica (AB) brasileira para a ampliação da discussão sobre sua oferta. Métodos: Estudo ecológico transversal realizado em 2020, a partir do sistema público brasileiro de informação em saúde do ano de 2019. Para análise, analisou-se a variável dependente quantidade de atendimentos, enquanto as variáveis independentes deram-se por território, Índice de Desenvolvimento Humano (IDH) e a cobertura da AB. Para as comparações estatísticas utilizaram-se os testes de qui-quadrado de Pearson e correlação de Spearman. Resultados: Considerando AB, secundária e terciária do Sistema Único de Saúde (SUS), a prevalência total de atendimentos em 2019 apresentou-se por 1.593.128. Separando e analisando exclusivamente a AB (n=51.352; 3.2%), a maior prevalência de atendimentos apresentou-se nas regiões Sudeste (n=15.210; 29,7%) e Nordeste (n=12.559; 24.4%), com ocorrências maiores de sessões de eletroestimulação (n=6.397; 12,4%) e de práticas corporais em Medicina Tradicional Chinesa (n=4.588; 8,9%). As correlações deram-se positivas entre atendimentos e população (r=0,62), e entre atendimentos e IDH (r=0,24). Conclusão: Evidenciou-se que a distribuição espacial das PICS na AB é desigual ao se considerar as prevalências de cada região. Já as correlações positivas podem representar a procura por alternativas de cuidado frente a condições crônicas, queixas musculoesqueléticas e insatisfação com a Medicina Moderna; fatores que geralmente provocam o aumento pela procura de PICS, principalmente em regiões onde o desenvolvimento social mais elevado favorece a autonomia da pessoa.


Objective:To analyze the spatial distribution of Integrative and Complementary Health Practices (Práticas Integrativas e Complementares em Saúde ­ PICS) in Brazil's Primary Health Care (PHC) to broaden the discussion about its offer. Methods: A cross-sectional ecologic study was carried out in 2020 using data from the Brazilian public health care information system dating from 2019. For the analysis, the dependent variable was the number of visits, and the independent variables were the territory, the Human Development Index (HDI) and PHC coverage. Pearson's chi-square and Spearman's correlation tests were used for statistical comparisons. Results: Thetotal prevalence rate of visits in 2019 was 1,593,128 in primary, secondary and tertiary care within the Unified Health System (Sistema Único de Saúde ­ SUS). When we analyzed exclusively and separately PHC (n=51,352; 3.2%), the highest rate of visits was found in the Southeast (n=15,210; 29.7%) and Northeast (n=12,559; 24.4%) regions, with higher rates of electrical stimulation sessions (n=6,397; 12.4%) and body practices in Traditional Chinese Medicine (n=4,588; 8.9%). Correlations were positive between visits and population (r=0.62) and between visits and HDI (r=0.24). Conclusion:It was evident that the spatial distribution of PICS in PHC is uneven when considering the prevalence rate of each region. The positive correlations may represent the search for alternative care in the face of chronic conditions, musculoskeletal complaints, and dissatisfaction with Modern Medicine. These factors generally cause an increase in the demand for PICS, especially in regions where higher social development favors individual autonomy.


Objetivo: Analizar la distribución espacial de las Prácticas Integrativas y Complementarias de Salud (PICS) de la Atención Básica (AB) brasileña para la ampliación de la discusión de su oferta. Métodos: Estudio ecológico transversal realizado en 2020 a partir del sistema público brasileño de información en salud del año 2019. Se analizó la variable dependiente "cantidad de consultas" mientras las variables independientes se dieron por el territorio, el Índice de Desarrollo Humano (IDH) y la cobertura de la AB. Para las comparaciones estadísticas se ha utilizado las pruebas de chi-cuadrado de Pearson y la correlación de Spearman. Resultados: Considerando la AB, secundaria y terciaria del Sistema Único de Salud (SUS), la prevalencia total de las consultas en 2019 ha sido de 1.593.128. Separando y analizando exclusivamente la AB (n=51.352; 3.2%), la mayor prevalencia de consultas se dio en las regiones Sudeste (n=15.210; 29,7%) y Noreste (n=12.559; 24.4%), con ocurrencias de más sesiones de electroestimulación (n=6.397; 12,4%) y de prácticas corporales de la Medicina Tradicional China (n=4.588; 8,9%). Las correlaciones han sido positivas entre las consultas y la población (r=0,62) y entre las consultas y el IDH (r=0,24). Conclusión: Se ha evidenciado que la distribución espacial de las PICS en la AB es desigual respecto las prevalencias de cada región. Las correlaciones positivas pueden representar la búsqueda de alternativas de cuidado para las condiciones crónicas, las quejas musculo esqueléticas y la insatisfacción con la Medicina Moderna; factores que, en general, llevan al mayor interés por las PICS, sobre todo en las regiones donde el desarrollo social más alto favorece la autonomía de la persona.

12.
Hippocampus ; 32(1): 38-54, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34843143

RESUMO

The hippocampus has been linked to memory encoding and spatial navigation, while the prefrontal cortex is associated with cognitive functions such as decision-making. These regions are hypothesized to communicate in tasks that demand both spatial navigation and decision-making processes. However, the electrophysiological signatures underlying this communication remain to be better elucidated. To investigate the dynamics of the hippocampal-prefrontal interactions, we have analyzed their local field potentials and spiking activity recorded from rats performing a spatial alternation task on a figure eight-shaped maze. We found that the phase coherence of theta peaked around the choice point area of the maze. Moreover, Granger causality revealed a hippocampus → prefrontal cortex directionality of information flow at theta frequency, peaking at starting areas of the maze, and on the reverse direction at delta frequency, peaking near the turn onset. Additionally, the patterns of phase-amplitude cross-frequency coupling within and between the regions also showed spatial selectivity, and hippocampal theta and prefrontal delta modulated not only gamma amplitude but also inter-regional gamma synchrony. Finally, we found that the theta rhythm dynamically modulated neurons in both regions, with the highest modulation at the choice area; interestingly, prefrontal cortex neurons were more strongly modulated by the hippocampal theta rhythm than by their local field rhythm. In all, our results reveal maximum electrophysiological interactions between the hippocampus and the prefrontal cortex near the decision-making period of the spatial alternation task, corroborating the hypothesis that a dynamic interplay between these regions takes place during spatial decisions.


Assuntos
Hipocampo , Ritmo Teta , Animais , Cognição , Hipocampo/fisiologia , Neurônios , Córtex Pré-Frontal/fisiologia , Ratos , Ritmo Teta/fisiologia
13.
Int J Sports Med ; 43(3): 254-261, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34388844

RESUMO

This study aimed to determine the relationship between indirect measures of aerobic power and muscular power with Frequency Speed of Kick Test performance using multiple sets (FSKTmult) in high-level taekwondo athletes. We used a known-group method to test differences in FSKTmult performance between two groups designated as lower and higher performance in both aerobic power and muscular power. In total, 42 international or national taekwondo athletes of both sexes performed the FSKTmult, Progressive Specific Taekwondo Test (PSTT), and countermovement jump (CMJ). Our results showed that average of the three CMJ was moderately correlated with FSKTmult performance (r=0.44); whereas PSTT and FSKTmult were highly correlated (r=0.83). Moreover, the groups formed by lower and higher performance of time to exhaustion in PSTT, as well as the average of CMJ were able to discriminate performance in the FSKTmult (p ≤0.05). The present study thus suggests that aerobic and muscle power are important for FSKTmult performance.


Assuntos
Desempenho Atlético , Artes Marciais , Atletas , Desempenho Atlético/fisiologia , Feminino , Humanos , Masculino , Artes Marciais/fisiologia , Força Muscular , Músculos
14.
Front Cell Dev Biol ; 9: 622610, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307340

RESUMO

The human immunodeficiency virus (HIV-1) modifies the host cell environment to ensure efficient and sustained viral replication. Key to these processes is the capacity of the virus to hijack ATPases, GTPases and the associated proteins that control intracellular protein trafficking. The functions of these energy-harnessing enzymes can be seized by HIV-1 to allow the intracellular transport of viral components within the host cell or to change the subcellular distribution of antiviral factors, leading to immune evasion. Here, we summarize how energy-related proteins deviate from their normal functions in host protein trafficking to aid the virus in different phases of its replicative cycle. Recent discoveries regarding the interplay among HIV-1 and host ATPases and GTPases may shed light on potential targets for pharmacological intervention.

15.
J Prosthet Dent ; 125(2): 294-299, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32115221

RESUMO

STATEMENT OF PROBLEM: Intraoral scanners (IOSs) have some inherent distortions caused by optical and/or software imperfections. However, how other factors such as operator experience, scan time, scanner type, and scan size influence scan accuracy is not clear. PURPOSE: The purpose of this in vitro study was to evaluate the trueness and precision of scans performed by 3 professionals with different levels of experience by using 2 IOSs. MATERIAL AND METHODS: Three operators with low, medium, and high levels of experience scanned a master model 10 times by using 2 IOSs (CEREC Omnicam; Dentsply Sirona and TRIOS 3; 3Shape), resulting in 10 standard tessellation language files for each group (N=60). Each standard tessellation language file was divided into 2 areas (prepared teeth and complete arch). Precision was evaluated by comparing the 10 scans from each examiner for each system. Trueness was evaluated by comparing each scan file with a reference scan obtained from a laboratory scanner (D2000; 3Shape). A 3D analysis software program (Geomagic Control; 3D Systems) was used to perform all the comparisons and superimpositions. The 3-way ANOVA test followed by the Tukey HSD test were used to assess precision and trueness. The 2-way ANOVA followed by the Tukey HSD test was used to assess scan time. The Pearson correlation test was performed between scan time and trueness for both scanners. An additional correlation was performed between scan time and number of images, as well as between number of images and trueness for the TRIOS 3. RESULTS: Statistically significant influences of operator (P<.001), scanner (P<.001), scan size (P<.001), operator and scan size (P<.001), and scanner and scan size (P<.001) were observed. The TRIOS 3 group reported higher precision than the CEREC Omnicam group for complete-arch scans (P<.001), although no difference was observed for scans of the prepared tooth. Medium- (P=.002) and low-experience operators (P<.001) reported lower precision for complete-arch scans performed with CEREC Omnicam when compared with TRIOS 3. The low-experience operator reported significantly worse results for complete-arch scans in comparison with the medium- (P=.008 and P<.001) and high-experience operators (P<.001 and P=.001), by using TRIOS 3 and CEREC Omnicam, respectively. Medium- and high-experience operators reported similar results among themselves. The CEREC Omnicam scanner reported lower trueness for complete-arch scans when compared with the prepared tooth (P<.001); for TRIOS 3, a difference was only observed for the low-experience operator when compared with the high-experience operator (P<.001). The CEREC Omnicam reported lower trueness than the TRIOS 3, except for the medium-experience operator with the prepared tooth scan. Comparing the trueness between operators and considering the same scanner and scan size, all groups were similar. The low-experience operator had a longer scanning time than the medium- and high-experience operators. For TRIOS 3, the low-experience operator obtained the highest number of images during each scan. CONCLUSIONS: The accuracy of intraoral scans was influenced by operator experience, type of IOSs, and scan size. More experienced operators and smaller scan sizes made for more accurate scans. In addition, more experienced operators made faster scans, and the TRIOS 3 was more accurate than the CEREC Omnicam for complete-arch scans.


Assuntos
Técnica de Moldagem Odontológica , Modelos Dentários , Desenho Assistido por Computador , Arco Dental , Imageamento Tridimensional
16.
Front Sports Act Living ; 3: 797604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34977570

RESUMO

Purpose: This study aimed to compare the oxygen consumption, lactate concentrations, and energy expenditure using three different intensities during the resistance training sessions. Methods: A total of 15 men (22.9 ± 2.61 years) experienced in resistance training underwent 3 sessions composed of 8 exercises (chest press, pec deck, squat, lat pull-down, biceps curl, triceps extension, hamstring curl, and crunch machine), which were applied in the same order. The weight lifted differed among the sessions [high session: 6 sets of 5 repetitions at 90% of 1-repetition maximum (1-RM); intermediary session: 3 sets of 10 repetitions at 75% of 1-RM; and low session: 2 sets of 15 repetitions at 60% of 1-RM]. The oxygen consumption (VO2)-during and after (excess post-exercise oxygen consumption (EPOC)) the session, blood lactate concentration, and energy expenditure (i.e., the sum of aerobic and anaerobic contributions, respectively) were assessed. Results: The VO2 significantly decreased in the function of the weight lifting (F (2.28) = 17.02; p < 0.01; η G 2 = 0.32). However, the aerobic contributions significantly increase in the function of the weight lifting (F (2.28) = 79.18; p < 0.01; η G 2 = 0.75). The anaerobic contributions were not different among the sessions (p > 0.05; η G 2 < 0.01). Thus, the total energy expenditure during the session (kcal) significantly increased in the function of the weight lifting (F (2.28) = 86.68; p < 0.01; η G 2 = 0.75). The energy expenditure expressed in time unit (kcal·min-1) was higher in low session than in high session (F (2.28) = 6.20; p < 0.01; η G 2 = 0.15). Conclusion: The weight lifted during resistance training-induced different physiological responses, which induced higher energy expenditure per unit of time during the low session.

17.
mBio ; 11(5)2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994321

RESUMO

Human respiratory syncytial virus (HRSV) envelope glycoproteins traffic to assembly sites through the secretory pathway, while nonglycosylated proteins M and N are present in HRSV inclusion bodies but must reach the plasma membrane, where HRSV assembly happens. Little is known about how nonglycosylated HRSV proteins reach assembly sites. Here, we show that HRSV M and N proteins partially colocalize with the Golgi marker giantin, and the glycosylated F and nonglycosylated N proteins are closely located in the trans-Golgi, suggesting their interaction in that compartment. Brefeldin A compromised the trafficking of HRSV F and N proteins and inclusion body sizes, indicating that the Golgi is important for both glycosylated and nonglycosylated HRSV protein traffic. HRSV N and M proteins colocalized and interacted with sorting nexin 2 (SNX2), a retromer component that shapes endosomes in tubular structures. Glycosylated F and nonglycosylated N HRSV proteins are detected in SNX2-laden aggregates with intracellular filaments projecting from their outer surfaces, and VPS26, another retromer component, was also found in inclusion bodies and filament-shaped structures. Similar to SNX2, TGN46 also colocalized with HRSV M and N proteins in filamentous structures at the plasma membrane. Cell fractionation showed enrichment of SNX2 in fractions containing HRSV M and N proteins. Silencing of SNX1 and 2 was associated with reduction in viral proteins, HRSV inclusion body size, syncytium formation, and progeny production. The results indicate that HRSV structural proteins M and N are in the secretory pathway, and SNX2 plays an important role in the traffic of HRSV structural proteins toward assembly sites.IMPORTANCE The present study contributes new knowledge to understand HRSV assembly by providing evidence that nonglycosylated structural proteins M and N interact with elements of the secretory pathway, shedding light on their intracellular traffic. To the best of our knowledge, the present contribution is important given the scarcity of studies about the traffic of HRSV nonglycosylated proteins, especially by pointing to the involvement of SNX2, a retromer component, in the HRSV assembly process.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Interações entre Hospedeiro e Microrganismos , Proteínas do Nucleocapsídeo/metabolismo , Vírus Sincicial Respiratório Humano/fisiologia , Proteínas Virais/metabolismo , Montagem de Vírus , Precursor de Proteína beta-Amiloide/genética , Proteínas de Transporte , Complexo de Golgi/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Células HeLa , Humanos , Transporte Proteico
18.
J Exp Med ; 217(12)2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32926098

RESUMO

Severe COVID-19 patients develop acute respiratory distress syndrome that may progress to cytokine storm syndrome, organ dysfunction, and death. Considering that neutrophil extracellular traps (NETs) have been described as important mediators of tissue damage in inflammatory diseases, we investigated whether NETs would be involved in COVID-19 pathophysiology. A cohort of 32 hospitalized patients with a confirmed diagnosis of COVID-19 and healthy controls were enrolled. The concentration of NETs was augmented in plasma, tracheal aspirate, and lung autopsies tissues from COVID-19 patients, and their neutrophils released higher levels of NETs. Notably, we found that viable SARS-CoV-2 can directly induce the release of NETs by healthy neutrophils. Mechanistically, NETs triggered by SARS-CoV-2 depend on angiotensin-converting enzyme 2, serine protease, virus replication, and PAD-4. Finally, NETs released by SARS-CoV-2-activated neutrophils promote lung epithelial cell death in vitro. These results unravel a possible detrimental role of NETs in the pathophysiology of COVID-19. Therefore, the inhibition of NETs represents a potential therapeutic target for COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Armadilhas Extracelulares/fisiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Células A549 , Adulto , Enzima de Conversão de Angiotensina 2 , COVID-19 , Morte Celular , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Células Epiteliais/patologia , Células Epiteliais/virologia , Feminino , Células HeLa , Humanos , Masculino , Ativação de Neutrófilo , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/sangue , Pneumonia Viral/patologia , SARS-CoV-2 , Serina Proteases/metabolismo , Sucção , Traqueia/imunologia
19.
Biol Chem ; 401(10): 1153-1165, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32755098

RESUMO

Pancreatic ductal adenocarcinoma is one of the most aggressive tumors with a microenvironment marked by hypoxia and starvation. Galectin-3 has been evaluated in solid tumors and seems to present both pro/anti-tumor effects. So, this study aims to characterize the expression of Galectin-3 from pancreatic tumor cells and analyze its influence for cell survive and motility in mimetic microenvironment. For this, cell cycle and cell death were accessed through flow cytometry. Characterization of inside and outside Galectin-3 was performed through Real-Time Quantitative Reverse Transcription PCR (qRT-PCR), immunofluorescence, Western blot, and ELISA. Consequences of Galectin-3 extracellular inhibition were investigated using cell death and scratch assays. PANC-1 showed increased Galectin-3 mRNA expression when cultivated in hypoxia for 24 and 48 h. After 24 h in simultaneously hypoxic/deprived incubation, PANC-1 shows increased Galectin-3 protein and secreted levels. For Mia PaCa-2, cultivation in deprivation was determinant for the increasing in Galectin-3 mRNA expression. When cultivated in simultaneously hypoxic/deprived condition, Mia PaCa-2 also presented increasing for the Galectin-3 secreted levels. Treatment of PANC-1 cells with lactose increased the death rate when cells were incubated simultaneously hypoxic/deprived condition. Therefore, it is possible to conclude that the microenvironmental conditions modulate the Galectin-3 expression on the transcriptional and translational levels for pancreatic cancer cells.


Assuntos
Proteínas Sanguíneas/metabolismo , Galectinas/metabolismo , Nutrientes/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/isolamento & purificação , Ciclo Celular , Morte Celular , Hipóxia Celular , Galectinas/genética , Galectinas/isolamento & purificação , Humanos , Neoplasias Pancreáticas/patologia , Células Tumorais Cultivadas , Microambiente Tumoral
20.
PLoS Pathog ; 16(3): e1008435, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32210480

RESUMO

A striking feature of human visceral leishmaniasis (VL) is chronic inflammation in the spleen and liver, and VL patients present increased production levels of multiple inflammatory mediators, which contribute to tissue damage and disease severity. Here, we combined an experimental model with the transcriptional profile of human VL to demonstrate that the TLR4-IFN-ß pathway regulates the chronic inflammatory process and is associated with the asymptomatic form of the disease. Tlr4-deficient mice harbored fewer parasites in their spleen and liver than wild-type mice. TLR4 deficiency enhanced the Th1 immune response against the parasite, which was correlated with an increased activation of dendritic cells (DCs). Gene expression analyses demonstrated that IRF1 and IFN-ß were expressed downstream of TLR4 after infection. Accordingly, IRF1- and IFNAR-deficient mice harbored fewer parasites in the target organs than wild-type mice due to having an increased Th1 immune response. However, the absence of TLR4 or IFNAR increased the serum transaminase levels in infected mice, indicating the presence of liver damage in these animals. In addition, IFN-ß limits IFN-γ production by acting directly on Th1 cells. Using RNA sequencing analysis of human samples, we demonstrated that the transcriptional signature for the TLR4 and type I IFN (IFN-I) pathways was positively modulated in asymptomatic subjects compared with VL patients and thus provide direct evidence demonstrating that the TLR4-IFN-I pathway is related to the nondevelopment of the disease. In conclusion, our results demonstrate that the TLR4-IRF1 pathway culminates in IFN-ß production as a mechanism for dampening the chronic inflammatory process and preventing immunopathology development.


Assuntos
Fator Regulador 1 de Interferon/imunologia , Interferon beta/imunologia , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Células Th1/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Fator Regulador 1 de Interferon/genética , Interferon beta/genética , Leishmaniose Visceral/genética , Leishmaniose Visceral/patologia , Camundongos , Camundongos Knockout , Células Th1/patologia , Receptor 4 Toll-Like/genética
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