22 research outputs found
Molecular mechanism of inhibiting the SARS-CoV-2 cell entry facilitator TMPRSS2 with camostat and nafamostat
No full textThe entry of the coronavirus SARS-CoV-2 into human lung cells can be inhibited by the approved drugs camostat and nafamostat. Here we elucidate the molecular mechanism of these drugs by combining experiments and simulations. In vitro assays confirm that both drugs inhibit the human protein TMPRSS2, a SARS-Cov-2 spike protein activator. As no experimental structure is available, we provide a model of the TMPRSS2 equilibrium structure and its fluctuations by relaxing an initial homology structure with extensive 330 microseconds of all-atom molecular dynamics (MD) and Markov modeling. Through Markov modeling, we describe the binding process of both drugs and a metabolic product of camostat (GBPA) to TMPRSS2, reaching a Michaelis complex (MC) state, which precedes the formation of a long-lived covalent inhibitory state. We find that nafamostat has a higher MC population than camostat and GBPA, suggesting that nafamostat is more readily available to form the stable covalent enzyme-substrate intermediate, effectively explaining its high potency. This model is backed by our in vitro experiments and consistent with previous virus cell entry assays. Our TMPRSS2-drug structures are made public to guide the design of more potent and specific inhibitors
Introduction
No full textContemporary multiculturalist anthropology overlooks huge disparities in population size as well as ethnographic actors’ own scaling of their practices and imaginations. Arguing that scale-blindness limits our understanding of key issues in forager studies and distorts the insights these societies offer us, the introduction develops a theoretical framework for integrating scaling into their analysis. Drawing from studies of kinship, animism, multiscalar anthropology, imagined communities, and notions of being-with, it develops the idea of pluripresence. This theoretical approach is applied in the volume to the ethnography of a South Asian foraging people known as Nayaka, whom the author has studied since the late 1970s. They are introduced as an exemplar of hunter-gatherer peoples, who are among the tiniest communities studied by ethnographers, and as one of many indigenous peoples who have no ethnonyms for themselves and, instead, use terms of kinship and shared humanity as their we-designations. Their plural modes especially are eclipsed by the scale-blind regime, which, in fact, is large-scale inflected since the ethnonyms and other representational conventions (e.g., maps) that are indispensable in anthropology’s large-scale project embody modern imaginations of communities. The introduction explains the volume’s strategy for studying this tiny community.</p
Deletion of SPINK7 by CRISPR/Cas9 Elicits Pro-Inflammatory and Impaired Epithelial Barrier Responses in Esophageal Epithelial Cells
No full text
Rab5 is critical for SNAP23 regulated granule-granule fusion during compound exocytosis
No full textAbstractCompound exocytosis is considered the most massive mode of exocytosis, during which the membranes of secretory granules (SGs) fuse with each other to form a channel through which the entire contents of their granules is released. The underlying mechanisms of compound exocytosis remain largely unresolved. Here we show that the small GTPase Rab5, a known regulator of endocytosis, is pivotal for compound exocytosis in mast cells. Silencing of Rab5 shifts receptor-triggered secretion from a compound to a full exocytosis mode, in which SGs individually fuse with the plasma membrane. Moreover, we show that Rab5 is essential for FcεRI-triggered association of the SNARE protein SNAP23 with the SGs. Direct evidence is provided for SNAP23 involvement in homotypic SG fusion that occurs in the activated cells. Finally, we show that this fusion event is prevented by inhibition of the IKKβ2 kinase, however, neither a phosphorylation-deficient nor a phosphomimetic mutant of SNAP23 can mediate homotypic SG fusion in triggered cells. Taken together our findings identify Rab5 as a heretofore-unrecognized regulator of compound exocytosis that is essential for SNAP23-mediated granule-granule fusion. Our results also implicate phosphorylation cycles in controlling SNAP23 SNARE function in homotypic SG fusion.</jats:p
The Bordetella type III secretion system effector BteA targets host eosinophil-epithelial signaling to promote IL-1Ra expression and persistence
No full textAbstract Eosinophils are traditionally associated with parasitic infections and allergic pathologies. However, emerging evidence highlights their underappreciated roles during mucosal bacterial infections. Using in vivo and in vitro approaches, we demonstrate that classical Bordetella spp. increase IL-1Ra production from both epithelial cells and eosinophils to facilitate immune evasion and persistence. Depletion of IL-1Ra via genetic knockout or antibody neutralization in vivo accelerated bacterial clearance. We show that the Bordetella type III secretion system (T3SS) effector, BteA, promotes AkT/mTOR pathway activation leading to IL-1Ra expression, which is independent of IL-1α or IL-1β production. Together, our findings uncover the molecular mechanism by which classical Bordetellae exploit host epithelial-eosinophil signaling to exclusively upregulate IL-1Ra and dampen host inflammation for persistence. These results provide therapeutic targets for controlling disease caused by long-term Bordetella infection and may have broader applications for other respiratory pathogens. Moreover, these insights expand our understanding of eosinophil function beyond traditional paradigms
Conhecimento tradicional indígena: revitalização de expressões culturais do Povo Kaingáng da Terra Indígena Serrinha/RS e da Aldeia Condá/SC
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas, Programa de Pós-Graduação em Direito, Florianópolis, 2011A legislação pátria possui um sistema específico de proteção à diversidade cultural derivado do princípio do multiculturalismo consagrado na Carta Magna de 1988. Todavia, a transformação da letra da lei em práticas referenciadas na livre-determinação dos Povos Indígenas, na valorização, promoção e proteção das diferentes expressões culturais ainda carece de avanços em sua implementação e se constitui em um desafio a ser enfrentado, embora exemplos exitosos, nesse sentido, existam e devam ser multiplicados, com a participação plena e efetiva dos Povos Indígenas. Neste sentido, a presente dissertação propõe o estudo da temática relacionada ao conhecimento tradicional indígena a partir do reconhecimento do multiculturalismo, em marcos jurídicos internacionais e, especialmente, na Constituição Federal de 1988, visando tecer contribuições à reflexão teórico-prática acerca da proteção dos direitos culturais e patrimônio cultural dos Povos Indígenas. Neste contexto, visa-se apresentar iniciativas ou boas práticas promovidas pelos Kanhgág Kófa (anciãos Kaingáng), em prol da revitalização de expressões culturais junto ao Povo Kaingáng. A exploração da temática se encontra embasada em referencial bibliográfico, como também em estudo de caso, amparado em relatos orais coletados no decorrer da atuação da autora junto aos Kanhgág Kófa.Abstract : The country legislation owns a specific system of protection to the cultural diversity, product of the beginning of multiculturalism enshrined in the Magna Carta 1988. However the transformation of letter of the law in practices reference in the free-determination of the Indian People, in the improving, promotion and protection of the different cultural expressions still need of progress in your implementation and challenge to be addressed although success examples, in this sense, there are and must be increased (multiply), with the complete and effective participation of the Indian People. In this sense, the present dissertation proposes the study of the theme related with lhe Indian Traditional knowledge since of de recognition of the multiculturalism capacity international legal, and, specially in the Federal Constitution of 1988 to theory-pratic reflexion about the protection of the cultural laws and cultural heritage of the Indian People. In this context, it intends to introduce initiatives or good pratics promotes by Kanhgág Kófa (old Kaingáng), in favour of the revitalization of cultural expressions near of Kaingáng People. The exploration of the theme find with emphasis in bibliographic referencial research as will one study of case, supported in oral accounts collected in the result of the acting of the author near the Kanhgág Kófa
Table1_Aryl hydrocarbon receptor and IL-13 signaling crosstalk in human keratinocytes and atopic dermatitis.xlsx
No full textIntroductionAtopic dermatitis (AD) is an allergic skin disease mediated by skin barrier impairment and IL-13-driven immune response. Activation of the aryl hydrocarbon receptor (AHR) has shown promise in early clinical trials for AD; however, the mechanism by which AHR partially ameliorates AD is not well known.MethodsGene expression data from human biopsies were analyzed, and compared to gene expression from RNA-sequencing in our in-vitro HaCaT cell model system. Western blot, ELISA qRT-PCR were used to further explore the relationship between AHR and IL-13 signaling in HaCaT cells.ResultsThe AHR target gene CYP1A1 was decreased in lesional skin compared with healthy control skin (p = 4.30 × 10−9). Single-cell RNA sequencing (scRNAseq) demonstrated increased AHR expression (p −4) and decreased CYP1A1 expression in lesional AD keratinocytes compared with healthy control keratinocytes (p DiscussionTogether, these data suggest that the AHR pathway is dysregulated in AD and that AHR modulates IL-13 downstream signaling in keratinocytes through genome-wide, transcriptional regulatory effects.</p
