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1.
J Periodontal Res ; 59(2): 267-279, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-37990413

RÉSUMÉ

OBJECTIVE: The present study was designed to investigate the role of macrophage migration inhibitory factor (MIF) in the exacerbation of pregestational periodontal disease (PGPD). BACKGROUND: Periodontitis (PT) is a severe stage of periodontal disease characterized by inflammation of the supporting tissues of the teeth, which usually worsens during pregnancy. MIF is a proinflammatory cytokine that is significantly elevated in periodontitis, both at the beginning and at the end of pregnancy. Although periodontitis usually presents with greater severity during pregnancy, the participation of MIF in the evolution of periodontitis has not been established. METHODS: To analyze the relevance of MIF in the exacerbation of PGPD, we employed a model of PGPD in WT and Mif-/- mice, both with a BALB/c genetic background. PT was induced with nylon suture ligatures placed supramarginally around the second upper right molar. For PGPD, PT was induced 2 weeks before mating. We evaluated histological changes and performed histometric analysis of the clinical attachment loss, relative expression of MMP-2 and MMP-13 by immunofluorescence, and relative expression of the cytokines mif, tnf-α, ifn-γ, and il-17 by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Our data revealed that periodontal tissue from PGPD WT mice produced a twofold increase in MIF compared with PT WT mice. Moreover, the evolution of periodontitis in Mif-/- mice was less severe than in PGDP WT mice. Periodontal tissue from Mif-/- mice with PGPD produced 80% less TNF-α and no IFN-γ, as well as 50% lower expression of matrix metalloproteinase (MMP)-2 and 25% less MMP-13 compared to WT PGDP mice. CONCLUSIONS: Our study suggests that MIF plays an important role in the exacerbation of periodontitis during pregnancy and that MIF is partially responsible for the inflammation associated with the severity of periodontitis during pregnancy.


Sujet(s)
Facteurs inhibiteurs de la migration des macrophages , Parodontite , Animaux , Femelle , Souris , Grossesse , Inflammation/métabolisme , Facteurs inhibiteurs de la migration des macrophages/métabolisme , Matrix Metalloproteinase 13 , Parodontite/métabolisme , Facteur de nécrose tumorale alpha
2.
Front Bioeng Biotechnol ; 11: 1294355, 2023.
Article de Anglais | MEDLINE | ID: mdl-38076419

RÉSUMÉ

We present in this work a kinetic model of the acetone-butanol-ethanol (ABE) fermentation based on enzyme kinetics expressions. The model includes the effect of the co-substrate NADH as a modulating factor of cellular metabolism. The simulations obtained with the model showed an adequate fit to the experimental data reported by several authors, matching or improving the results observed with previous models. In addition, this model does not require artificial mathematical strategies such as on-off functions to achieve a satisfactory fit of the ABE fermentation dynamics. The parametric sensitivity allowed to identify the direct glucose → acetyl-CoA → butyryl-CoA pathway as being more significant for butanol production than the acid re-assimilation pathway. Likewise, model simulations showed that the increase in NADH, due to glucose concentration, favors butanol production and selectivity, finding a maximum selectivity of 3.6, at NADH concentrations above 55 mM and glucose concentration of 126 mM. The introduction of NADH in the model would allow its use for the analysis of electrofermentation processes with Clostridium, since the model establishes a basis for representing changes in the intracellular redox potential from extracellular variables.

3.
Molecules ; 28(5)2023 Mar 06.
Article de Anglais | MEDLINE | ID: mdl-36903662

RÉSUMÉ

Intense exposure to UVB radiation incites excessive production of reactive oxygen species (ROS) and inflammation. The resolution of inflammation is an active process orchestrated by a family of lipid molecules that includes AT-RvD1, a specialized proresolving lipid mediator (SPM). AT-RvD1 is derived from omega-3, which presents anti-inflammatory activity and reduces oxidative stress markers. The present work aims to investigate the protective effect of AT-RvD1 on UVB-induced inflammation and oxidative stress in hairless mice. Animals were first treated with 30, 100, and 300 pg/animal AT-RvD1 (i.v.) and then exposed to UVB (4.14 J/cm2). The results showed that 300 pg/animal of AT-RvD1 could restrict skin edema, neutrophil and mast cell infiltration, COX-2 mRNA expression, cytokine release, and MMP-9 activity and restore skin antioxidant capacity as per FRAP and ABTS assays and control O2•- production, lipoperoxidation, epidermal thickening, and sunburn cells development. AT-RvD1 could reverse the UVB-induced downregulation of Nrf2 and its downstream targets GSH, catalase, and NOQ-1. Our results suggest that by upregulating the Nrf2 pathway, AT-RvD1 promotes the expression of ARE genes, restoring the skin's natural antioxidant defense against UVB exposition to avoid oxidative stress, inflammation, and tissue damage.


Sujet(s)
Antioxydants , Acide acétylsalicylique , Animaux , Souris , Antioxydants/pharmacologie , Acide acétylsalicylique/pharmacologie , Facteur-2 apparenté à NF-E2/métabolisme , Stress oxydatif , Inflammation , Acide docosahexaénoïque/pharmacologie , Rayons ultraviolets
4.
Angew Chem Int Ed Engl ; 62(21): e202302575, 2023 May 15.
Article de Anglais | MEDLINE | ID: mdl-36959093

RÉSUMÉ

The interfacial barrier of charge transfer from semiconductors to cocatalysts means that the photogenerated charges cannot be fully utilized, especially for the challenging water oxidation reaction. Using cobalt cubane molecules (Co4 O4 ) as water oxidation cocatalysts, we rationally assembled partially oxidized graphene (pGO), acting as a charge-transfer mediator, on the hole-accumulating {-101} facets of lead chromate (PbCrO4 ) crystal. The assembled pGO enables preferable immobilization of Co4 O4 molecules on the {-101} facets of the PbCrO4 crystal, which is favorable for the photogenerated holes transferring from PbCrO4 to Co4 O4 molecules. The surface charge-transfer efficiency of PbCrO4 was boosted by selective assembly of pGO between PbCrO4 and Co4 O4 molecules. An apparent quantum efficiency for photocatalytic water oxidation on the Co4 O4 /pGO/PbCrO4 photocatalyst exceeded 10 % at 500 nm. This strategy of rationally assembling charge-transfer mediator provides a feasible method for acceleration of charge transfer and utilization in semiconductor photocatalysis.

5.
Article de Anglais | MEDLINE | ID: mdl-36231567

RÉSUMÉ

Moral disengagement is a process of cognitive restructuring that allows individuals to disassociate from their internal moral standards and behave unethically without feeling distressed. It has been described as a key predictor of maladaptive behaviors (e.g., delinquency, aggression, and cyberbullying) and as a mediator between individual variables and unethical outcomes (e.g., empathy and aggression). We aimed to provide evidence of validity based on the internal structure, reliability, and correlations with other constructs of the most used instrument to measure disengagement from moral self-sanctions: Bandura's Mechanisms of Moral Disengagement Scale (MMDS). A non-probabilistic national sample of 528 Chilean adolescents from 14 to 18 years participated in the study. The results showed that the 10-item version of the MMDS had a unidimensional structure and good internal consistency. As expected, the MMDS-10 showed positive and medium correlations with abusive, violent antisocial, and delinquent behaviors and negative and medium associations with prosocial behavior and empathy. Additionally, moral disengagement fully mediated the relationship between empathy and violent antisocial behavior, supporting the hypothesis on moral disengagement as a self-regulatory cognitive process. The results confirm previous research, and the findings are discussed in terms of their implications for reducing the use of moral disengagement strategies in adolescence.


Sujet(s)
Cognition , Sens moral , Adolescent , Chili , Humains , Psychométrie , Reproductibilité des résultats , Enquêtes et questionnaires
6.
Front Immunol ; 13: 958820, 2022.
Article de Anglais | MEDLINE | ID: mdl-36189282

RÉSUMÉ

Chikungunya fever is a viral disease transmitted by mosquitoes of the genus Aedes. The infection is usually symptomatic and most common symptoms are fever accompanied by joint pain and swelling. In most cases symptoms subside within a week. However, severe prolonged and disabling joint pain, that may persist for several months, even years, are reported. Although the pathogenesis of Chikungunya infection is not fully understood, the evolution to severe disease seems to be associated with the activation of immune mechanisms and the action of inflammatory mediators. Platelets are recognized as inflammatory cells with fundamental activities in the immune response, maintenance of vascular stability and pathogenicity of several inflammatory and infectious diseases. Although the involvement of platelets in the pathogenesis of viral diseases has gained attention in recent years, their activation in Chikungunya has not been explored. The aim of this study was to analyze platelet activation and the possible role of platelets in the amplification of the inflammatory response during Chikungunya infection. We prospectively included 132 patients attended at the Quinta D'Or hospital and 25 healthy volunteers during the 2016 epidemic in Rio de Janeiro, Brazil. We observed increased expression of CD62P on the surface of platelets, as well as increased plasma levels of CD62P and platelet-derived inflammatory mediators indicating that the Chikungunya infection leads to platelet activation. In addition, platelets from chikungunya patients exhibit increased expression of NLRP3, caspase 4, and cleaved IL-1ß, suggestive of platelet-inflammasome engagement during chikungunya infection. In vitro experiments confirmed that the Chikungunya virus directly activates platelets. Moreover, we observed that platelet activation and soluble p-selectin at the onset of symptoms were associated with development of chronic forms of the disease. Collectively, our data suggest platelet involvement in the immune processes and inflammatory amplification triggered by the infection.


Sujet(s)
Fièvre chikungunya , Inflammasomes , Animaux , Arthralgie , Brésil , Caspases , Humains , Inflammasomes/métabolisme , Médiateurs de l'inflammation , Protéine-3 de la famille des NLR contenant un domaine pyrine/métabolisme , Sélectine P , Activation plaquettaire
7.
Br J Pharmacol ; 179(18): 4500-4515, 2022 09.
Article de Anglais | MEDLINE | ID: mdl-35716378

RÉSUMÉ

BACKGROUND AND PURPOSE: Gouty arthritis is characterized by an intense inflammatory response to monosodium urate crystals (MSU), which induces severe pain. Current therapies are often ineffective in reducing gout-related pain. Resolvin D1 (RvD1) is a specialized pro-resolving lipid mediator with anti-inflammatory and analgesic proprieties. In this study, we evaluated the effects and mechanisms of action of RvD1 in an experimental mouse model of gouty arthritis, an aim that was not pursued previously in the literature. EXPERIMENTAL APPROACH: Male mice were treated with RvD1 (intrathecally or intraperitoneally) before or after intraarticular stimulation with MSU. Mechanical hyperalgesia was assessed using an electronic von Frey aesthesiometer. Leukocyte recruitment was determined by knee joint wash cell counting and immunofluorescence. IL-1ß production was measured by ELISA. Phosphorylated NF-kB and apoptosis-associated speck-like protein containing CARD (ASC) were detected by immunofluorescence, and mRNA expression was determined by RT-qPCR. CGRP release was determined by EIA and immunofluorescence. MSU crystal phagocytosis was evaluated by confocal microscopy. KEY RESULTS: RvD1 inhibited MSU-induced mechanical hyperalgesia in a dose- and time-dependent manner by reducing leukocyte recruitment and IL-1ß production in the knee joint. Intrathecal RvD1 reduced the activation of peptidergic neurons and macrophages as well as silenced nociceptor to macrophage communication and macrophage function. CGRP stimulated MSU phagocytosis and IL-1ß production by macrophages. RvD1 downmodulated this phenomenon directly by acting on macrophages, and indirectly by inhibiting CGRP release and CGRP-dependent activation of macrophages. CONCLUSIONS AND IMPLICATIONS: This study reveals a hitherto unknown neuro-immune axis in gouty arthritis that is targeted by RvD1.


Sujet(s)
Goutte articulaire , Animaux , Goutte articulaire/induit chimiquement , Goutte articulaire/traitement médicamenteux , Peptide relié au gène de la calcitonine , Acide docosahexaénoïque , Hyperalgésie/traitement médicamenteux , Hyperalgésie/métabolisme , Inflammation/métabolisme , Activation des macrophages , Mâle , Souris , Neuro-immunomodulation , Neurones , Nocicepteurs/métabolisme , Douleur , Acide urique/composition chimique , Acide urique/pharmacologie
8.
Plant J ; 110(4): 1047-1067, 2022 05.
Article de Anglais | MEDLINE | ID: mdl-35220621

RÉSUMÉ

Mediator 17 (MED17) is a subunit of the Mediator complex that regulates transcription initiation in eukaryotic organisms. In yeast and humans, MED17 also participates in DNA repair, physically interacting with proteins of the nucleotide excision DNA repair system, but this function in plants has not been investigated. We studied the role of MED17 in Arabidopsis plants exposed to UV-B radiation. Our results demonstrate that med17 and OE MED17 plants have altered responses to UV-B, and that MED17 participates in various aspects of the DNA damage response (DDR). Comparison of the med17 transcriptome with that of wild-type (WT) plants showed that almost one-third of transcripts with altered expression in med17 plants were also changed by UV-B exposure in WT plants. Increased sensitivity to DNA damage after UV-B in med17 plants could result from the altered regulation of UV-B responsive transcripts but MED17 also physically interacts with DNA repair proteins, suggesting a direct role of this Mediator subunit during repair. Finally, we show that MED17 is necessary to regulate the DDR activated by ataxia telangiectasia and Rad3 related (ATR), and that programmed cell death 5 (PDCD5) overexpression reverts the deficiencies in DDR shown in med17 mutants. Our data demonstrate that MED17 is an important regulator of DDR after UV-B irradiation in Arabidopsis.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Arabidopsis/métabolisme , Protéines d'Arabidopsis/métabolisme , Altération de l'ADN , Réparation de l'ADN/génétique , Rayons ultraviolets
9.
Estilos clín ; 27(2)2022.
Article de Portugais | LILACS, Index Psychologie - Revues | ID: biblio-1436959

RÉSUMÉ

Este artigo discute os resultados de uma pesquisa que investigou uma experiência de formação inicial na qual licenciandos de diferentes cursos de Graduação atuavam como mediadores de estudantes com deficiência em uma escola comum. A partir do conceito psicanalítico de saber, buscou-se compreender como se dá a mobilização de saberes pelos mediadores e quais efeitos emergiram para a sua formação profissional como professores. Por meio de rodas de conversa e entrevistas individuais, os depoimentos dos participantes apontaram saberes em construção no percurso de cada mediador, o que os possibilitava encontrar saídas para os impasses presentes na relação com o outro no contexto escolar. Os mediadores reconheceram a importância dessa vivência para a formação, elencaram aproximações e paradoxos na articulação teoria-prática, além de expressarem suas próprias elaborações acerca desta experiência


Este artículo discute resultados de una investigación que estudió una experiencia de formación inicial donde licenciandos de diferentes cursos actuaban como mediadores de estudiantes com deficiência en una escuela común. A partir del concepto psicoanalítico del saber,se buscó compreender como se realiza la movilización de saberes por mediadores y qué efectos surgieron para su formación profesional. A través de círculos de charlas y entrevistas individuales, los testimonios de los participantes indicaron saberes en construcción en la trayectoria de cada mediador, posibilitándolos a encontrar salidas para obstáculos presentes en la relación con el outro en el contexto escolar. Los mediadores reconocieron la importancia de esa vivencia para la formación, mencionaron aproximaciones y contradicciones en la articulación teoría-práctica, además de expressar sus propias elaboraciones acerca de esta experiencia


This article discusses the results of a survey that investigated an initial training experience in which undergraduates from different undergraduate courses acted as mediators for students with disabilities in a regular school. Based on the psychoanalytical concept of knowledge, we sought to understand how knowledge is mobilized by these mediators and what effects have emerged for their professional development as teachers. Through round tables and individual interviews, the participants testimonies pointed to knowledge under construction in each mediator's path, which enabled them to find solutions to the impasses present in the relationship with the other in the school context.The mediators recognized the importance of this experience for training, listed approaches and paradoxes in the theory-practice articulation, in addition to expressing their own elaborations about this experience


Cet article discute les résultats d'une recherche qui a été menée sur une expérience de formation initiale dans laquelle des étudiants en licence de premier cycle sont intervenus comme des médiateurs des élèves handicapés. A partir du concept psychanalytique de savoir, nous cherchons à comprendre comment s'effectue la mobilisation de savoirs par les médiateurs et quels sont les effets qui en ont émergé pour leur formation professionnelle. Les témoignages des participants ont indiqué des savoirs en construction dans le parcours de chaque médiateur, ce qui leur permettait de trouver des solutions aux impasses présentes dans la relation avec l'autre en contexte scolaire. Les médiateurs ont reconnu l'importance de cette expérience pour leur formation, ils ont énuméré des approches et des paradoxes dans l'articulation théorie-pratique


Sujet(s)
Humains , Mâle , Femelle , Enseignement spécialisé , Formation Professionnelle , Psychanalyse , Négociation , Enseignants
10.
Front Mol Biosci ; 8: 614728, 2021.
Article de Anglais | MEDLINE | ID: mdl-34820418

RÉSUMÉ

The SARS-CoV-2 is the causative agent of the COVID-19 pandemic. The data available about COVID-19 during pregnancy have demonstrated placental infection; however, the mechanisms associated with intrauterine transmission of SARS-CoV-2 is still debated. Intriguingly, while canonical SARS-CoV-2 cell entry mediators are expressed at low levels in placental cells, the receptors for viruses that cause congenital infections such as the cytomegalovirus and Zika virus are highly expressed in these cells. Here we analyzed the transcriptional profile (microarray and single-cell RNA-Seq) of proteins potentially interacting with coronaviruses to identify non- canonical mediators of SARS-CoV-2 infection and replication in the placenta. Despite low levels of the canonical cell entry mediators ACE2 and TMPRSS2, we show that cells of the syncytiotrophoblast, villous cytotrophoblast, and extravillous trophoblast co-express high levels of the potential non-canonical cell-entry mediators DPP4 and CTSL. We also found changes in the expression of DAAM1 and PAICS genes during pregnancy, which are translated into proteins also predicted to interact with coronaviruses proteins. These results provide new insight into the interaction between SARS-CoV-2 and host proteins that may act as non-canonical routes for SARS-CoV-2 infection and replication in the placenta cells.

11.
Inflammopharmacology ; 29(5): 1603-1612, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34405339

RÉSUMÉ

BACKGROUND: The interaction of Cryptococcus neoformans with airway epithelial cells is crucial for the establishment of cryptococcosis. Aspirin-triggered-resolvin D1 (AT-RvD1) is a lipid mediator produced during the resolution of inflammation and demonstrates anti-inflammatory and pro-resolution effects in several inflammatory experimental models including in the airways. METHOD: Here, we evaluated the effects of AT-RvD1 (1, 10 or 100 nM) on human bronchial epithelial cells (BEAS-2B) stimulated with C. neoformans (1, 10 or 100 multiplicities of infection; MOI). RESULTS: After 24 h, C. neoformans (all MOI) demonstrated no cytotoxic effects and increased IL-8 production on BEAS-2B cells when compared to controls. In addition, C. neoformans (MOI 100) increased the concentration of IL-6, but not of IL-10. AT-RvD1 (100 nM) significantly reduced the concentration of IL-8 and IL-6 and increased IL-10 production in C. neoformans-stimulated BEAS-2B cells. C. neoformans increased the phosphorylation of NF-κB and ERK1/2, and ALX/FPR2 expression. AT-RvD1 reduced the activation of NF-kB without altering the ERK1/2 and ALX/FPR2 expression. The anti-inflammatory effects of AT-RvD1 were dependent on the ALX/FPR2, once its antagonist (BOC2) reversed its anti-inflammatory effects. No alteration on the fungal burden as well as interactions with BEAS-2B cells was observed by AT-RvD1. CONCLUSION: AT-RvD1 demonstrated significant anti-inflammatory effects in bronchial epithelial cells infected with C. neoformans without affecting the development of C. neoformans infection in the airways. TRIAL REGISTRATION: Not applicable.


Sujet(s)
Anti-inflammatoires/pharmacologie , Cryptococcose/traitement médicamenteux , Acide docosahexaénoïque/pharmacologie , Inflammation/traitement médicamenteux , Anti-inflammatoires/administration et posologie , Bronches/cytologie , Bronches/microbiologie , Bronches/anatomopathologie , Lignée cellulaire , Cryptococcose/anatomopathologie , Cryptococcus neoformans/isolement et purification , Acide docosahexaénoïque/administration et posologie , Relation dose-effet des médicaments , Cellules épithéliales/effets des médicaments et des substances chimiques , Cellules épithéliales/microbiologie , Cellules épithéliales/anatomopathologie , Humains , Inflammation/microbiologie
12.
Front Neurosci ; 15: 628836, 2021.
Article de Anglais | MEDLINE | ID: mdl-34366767

RÉSUMÉ

Insomnia is a widespread neuropsychological sleep-related disorder known to result in various predicaments including cognitive impairments, emotional distress, negative thoughts, and perceived sleep insufficiency besides affecting the incidence and aggravation of other medical disorders. Despite the available insomnia-related theoretical cognitive models, clinical studies, and related guidelines, an evidence-based conceptual framework for a personalized approach to insomnia seems to be lacking. This study proposes a conceptual cognitive framework (CCF) providing insight into cognitive mechanisms involved in the predisposition, precipitation, and perpetuation of insomnia and consequent cognitive deficits. The current CCF for insomnia relies on evaluative conditional learning and appraisal which generates negative valence (emotional value) and arousal (cognitive value). Even with the limitations of this study, the suggested methodology is well-defined, reproducible, and accessible can help foster future high-quality clinical databases. During clinical insomnia but not the neutral one, negative mood (trait-anxiety) causes cognitive impairments only if mediating with a distorted perception of insomnia ( Ind-1 = 0.161, 95% CI 0.040-0.311). Further real-life testing of the CCF is intended to formulate a meticulous, decision-supporting platform for clinical interventions. Furthermore, the suggested methodology is expected to offer a reliable platform for CCF-development in other cognitive impairments and support the causal clinical data models. It may also improve our knowledge of psychological disturbances and complex comorbidities to help design rehabilitation interventions and comprehensive frameworks in line with the "preventive medicine" policies.

13.
Chemosphere ; 279: 130525, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-33866102

RÉSUMÉ

This work focuses on the treatment of gaseous perchloroethylene (PCE) using electro-scrubbing with diamond electrodes and cobalt mediators. PCE was obtained by direct desorption from an aqueous solution containing 150 mg L-1, trying to a real pollution case. The electro-scrubber consisted of a packed absorption column connected with an undivided electrochemical cell. Diamond anodes supported on two different substrates (tantalum and silicon) were used and the results indicated that Ta/BDD was more successful in the production of Co (III) species and in the degradation of PCE. Three experimental systems were studied for comparison purposes: absorbent free of Co (III) precursors, absorbent containing Co (III) precursors, and absorbent containing Co (III) precursors undergoing previous electrolysis to the electro-scrubbing to facilitate the accumulation of oxidants. The most successful option was the last, confirming the important role of mediated electrochemical processes in the degradation of PCE. Trichloroacetic acid (TCA) and carbon tetrachloride (CCl4) were found as the primary reaction products and ethyl chloroacetate esters were also identified. A comprehensive mechanism of the processes happening inside electro-scrubber is proposed.


Sujet(s)
Tétrachloroéthylène , Polluants chimiques de l'eau , Cobalt , Diamant , Électrodes , Électrolyse , Gaz , Oxydoréduction
14.
New Phytol ; 229(3): 1278-1288, 2021 02.
Article de Anglais | MEDLINE | ID: mdl-33034045

RÉSUMÉ

Phosphate (Pi ) is a critical macronutrient for the biochemical and molecular functions of cells. Under phosphate limitation, plants manifest adaptative strategies to increase phosphate scavenging. However, how low phosphate sensing links to the transcriptional machinery remains unknown. The role of the MEDIATOR (MED) transcriptional co-activator, through its MED16 subunit in Arabidopsis root system architecture remodeling in response to phosphate limitation was assessed. Its critical function acting over the SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1)-ALUMINUM-ACTIVATED MALATE TRANSPORT1 (ALMT1) signaling module was tested through a combination of genetic, biochemical, and genome-wide transcriptomic approaches. Root system configuration in response to phosphate scarcity involved MED16 functioning, which modulates the expression of a large set of low-phosphate-induced genes that respond to local and systemic signals in the Arabidopsis root tip, including those directly activated by STOP1. Biomolecular fluorescence complementation analysis suggests that MED16 is required for the transcriptional activation of STOP1 targets, including the membrane permease ALMT1, to increase malate exudation in response to low phosphate. Our results unveil the function of a critical transcriptional component, MED16, in the root adaptive responses to a scarce plant macronutrient, which helps understanding how plant cells orchestrate root morphogenesis to gene expression with the STOP1-ALMT1 module.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Arabidopsis/génétique , Arabidopsis/métabolisme , Protéines d'Arabidopsis/génétique , Protéines d'Arabidopsis/métabolisme , Régulation de l'expression des gènes végétaux , Phosphates/métabolisme , Racines de plante/métabolisme , Transactivateurs , Facteurs de transcription/génétique
15.
Rev. peru. med. exp. salud publica ; 37(2): 220-228, abr.-jun. 2020. tab, graf
Article de Espagnol | LILACS | ID: biblio-1127161

RÉSUMÉ

RESUMEN Objetivos: Relacionar entre sí los eventos histopatológicos de malaria placentaria (MP), el comportamiento de células inmunitarias y la expresión de genes asociados a citoquinas, hipoxia, inflamación y angiogénesis en placentas con o sin infección plasmodial. Materiales y métodos: Diseño transversal, con tres grupos independientes. Las mujeres y sus placentas fueron captadas en 2009-2016, en los hospitales de Puerto Libertador y Tierralta, noroccidente de Colombia. El tamaño muestral se definió por conveniencia. El diagnóstico malárico se basó en PCR cuantitativa en tiempo real. Resultados: Se estudiaron 20 casos con MP por P. vivax (MP-V), 20 casos de MP por P. falciparum (MP-F) y 19 sin MP; 95% de los casos de MP son infección plasmodial placentaria submicroscópica (IPPS). Los tres grupos difieren en frecuencia y cantidad de eventos histopatológicos. Los mediadores de procesos fisiológicos presentaron diferencia significativa entre grupos, excepto IL-2, VEGF, VEGFR-1 y C5a. Conclusiones: Las placentas con infección difieren claramente de las no infectadas. P. vivax se comporta tan patógeno como P. falciparum. Se resalta la aproximación al abordaje integral del problema de MP. La infección plasmodial placentaria submicroscópica causa alteraciones tisulares y en mediadores fisiológicos como lo hace la infección microscópica, aunque probablemente en menor grado.


ABSTRACT Objetives: To relate histopathological events of placental malaria (PM), immune cell behavior and gene expression associated with cytokines, hypoxia, inflammation and angiogenesis in placentas with or without plasmodial infection. Materials and methods: Transversal design, with three independent groups. Women were recruited, and their placentas were collected in 2009-2016, in the hospitals of Puerto Libertador and Tierralta, northwestern Colombia. The sample size was defined by convenience. The malaria diagnosis was based on real-time quantitative PCR. Results: We studied 20 cases of PM by P. vivax (PM-V), 20 cases of PM by P. falciparum (PM-F) and 19 without PM; 95% of the cases of PM are submicroscopic placental plasmodial infection (SPPI). The three groups differ in frequency and number of histopathological events. Physiological process mediators showed significant difference between groups, except IL-2, VEGF, VEGFR-1 and C5a. Conclusions: Infected placentas are clearly different from uninfected ones. P. vivax behaves as pathogenic as P. falciparum. The approximation to the integral approach of the problem of PM is underlined. Submicroscopic placental plasmodial infection causes tissue and physiological mediator alterations as does microscopic infection, although probably to a lesser degree.


Sujet(s)
Humains , Femelle , Colombie , Phénomènes physiologiques , Paludisme , Anatomopathologie , Placenta , Placenta/parasitologie , Placenta/anatomopathologie , Plasmodium , Paludisme à Plasmodium falciparum , Paludisme/anatomopathologie
16.
Vínculo (São Paulo, Online) ; 17(1): 119-137, jan.-jun. 2020.
Article de Portugais | Index Psychologie - Revues, LILACS | ID: biblio-1127524

RÉSUMÉ

O objetivo geral deste trabalho é relatar a experiência de um grupo operativo temático com universitários que utilizou uma peça literária (conto) como objeto mediador, problematizando o uso deste dispositivo como um meio de cuidado em saúde mental na universidade. Realiza-se a análise de uma sessão do grupo operativo com o tema "família" à luz do referencial teórico da psicanálise vincular e do trabalho com grupos em instituições. Resultados: a constituição dos grupos levou em consideração as especificidades do público universitário e o vínculo com a instituição; o conto é um objeto cultural pré-constituído que mobiliza o pré-consciente e favorece os processos de simbolização; a escolha do conto como objeto mediador nos grupos relatados está em consonância com a tarefa primária da instituição universitária; o dispositivo apresentado constituiu-se como espaço de simbolização das experiências vividas na universidade e nas relações interpessoais, com potencial para a elaboração do sofrimento psíquico do jovem universitário. O grupo mediado por contos mostrou-se como um dispositivo de cuidado em saúde mental dos universitários a ser investigado e sistematizado, tendo em vista a ampliação da preocupação com os agravos à saúde mental na instituição universitária.


The general objective of this paper is to report the experience of a thematic operative group with university students who used a literary piece (short story) as a mediator object, problematizing the use of this device as a means of mental health care in the university. It is performed the analysis of a session of the operative group with the theme "family" in the light of the theoretical framework of psychoanalysis linkage and the work with groups in institutions. Results: the constitution of the groups took into account the specificities of the university public and the bond with the institution; the short story is a pre-constituted cultural object that mobilizes the preconscious and favors the processes of symbolization; the choice of the short story as a mediator object in the reported groups is in line with the primary task of the university institution; the presented device was constituted as a space of symbolization of the experiences lived in the university and in the interpersonal relations, with potential for the elaboration of the psychic suffering of the young university student. The group mediated by short stories proved to be a mental health care device for university students to be investigated and systematized, with a view to increasing concern about mental health problems in the university institution.


El objetivo general de este trabajo es informar la experiencia de un grupo operativo temático con estudiantes universitarios que utilizaron una pieza literaria (cuento) como objeto mediador, problematizando el uso de este dispositivo como un medio de atención de salud mental en la universidad. El análisis de una sesión del grupo operativo con el tema "familia" se realiza a la luz del marco teórico del psicoanálisis vincular y del trabajo con grupos en instituciones. Resultados: la constitución de los grupos tuvo en cuenta las especificidades del público universitario y el vínculo con la institución; el cuento es un objeto cultural preconstituido que estimula el preconsciente y favorece los procesos de simbolización; la elección del cuento como objeto mediador en los grupos informados está en línea con la tarea principal de la institución universitaria; el dispositivo presentado se constituyó como un espacio de simbolización de las experiencias vividas en la universidad y en las relaciones interpersonales, con potencial para la elaboración del sufrimiento psíquico del joven universitario. El grupo mediado por cuentos demostró ser un dispositivo de cuidado en la salud mental para estudiantes universitarios para ser investigado y sistematizado, tiendo en cuenta el aumento de la preocupación por los problemas de salud mental en la institución universitaria.


Sujet(s)
Humains , Mâle , Femelle , Anxiété , Psychanalyse , Adaptation sociale , Stress psychologique , Étudiants , Universités , Santé mentale , Santé des Élèves , Relations interpersonnelles , Attachement à l'objet
17.
Plant Cell Environ ; 43(8): 1989-1999, 2020 08.
Article de Anglais | MEDLINE | ID: mdl-32400913

RÉSUMÉ

Plants adapt to soil injury and biotic stress via cell regeneration. In Arabidopsis, root tip damage by genotoxic agents, antibiotics, UV light and cutting induces a program that recovers the missing tissues through activation of stem cells and involves ethylene response factor 115 (ERF115), which triggers cell replenishment. Here, we show that mutation of the gene encoding an MED18 subunit of the transcriptional MEDIATOR complex and chromate [Cr(VI)], an environmental pollutant, synergistically trigger a developmental program that enables the splitting of the meristem in vivo to produce twin roots. Expression of the quiescent centre gene marker WOX5, auxin-inducible DR5:GFP reporter and the ERF115 factor traced the changes in cell identity during the conversion of single primary root meristems into twin roots and were induced in an MED18 and chromate-dependent manner during the root twinning events, which also required auxin redistribution and signalling mediated by IAA14/SOLITARY ROOT (SLR1). Splitting of the root meristem allowed dichotomous root branching in Arabidopsis, a poorly understood process in which stem cells may act to enable whole organ regeneration.


Sujet(s)
Protéines d'Arabidopsis/génétique , Arabidopsis/génétique , Complexe médiateur/génétique , Méristème/génétique , Racines de plante/génétique , Arabidopsis/effets des médicaments et des substances chimiques , Protéines d'Arabidopsis/métabolisme , Chrome/pharmacologie , Régulation de l'expression des gènes végétaux , Protéines à homéodomaine/génétique , Acides indolacétiques/métabolisme , Complexe médiateur/métabolisme , Méristème/effets des médicaments et des substances chimiques , Mutation , Racines de plante/effets des médicaments et des substances chimiques , Racines de plante/croissance et développement , Végétaux génétiquement modifiés , Facteurs de transcription/génétique
18.
Transcription ; 11(3-4): 160-171, 2020.
Article de Anglais | MEDLINE | ID: mdl-32406332

RÉSUMÉ

The advent of novel high-throughput sequencing techniques has revealed that eukaryotic genomes are massively transcribed although only a small fraction of RNAs exhibits protein-coding capacity. In the last years, long noncoding RNAs (lncRNAs) have emerged as regulators of eukaryotic gene expression in a wide range of molecular mechanisms. Plant lncRNAs can be transcribed by alternative RNA polymerases, acting directly as long transcripts or can be processed into active small RNAs. Several lncRNAs have been recently shown to interact with chromatin, DNA or nuclear proteins to condition the epigenetic environment of target genes or modulate the activity of transcriptional complexes. In this review, we will summarize the recent discoveries about the actions of plant lncRNAs in the regulation of gene expression at the transcriptional level.


Sujet(s)
Plantes/génétique , ARN long non codant/génétique , Transcription génétique/génétique , Séquençage nucléotidique à haut débit , Plantes/métabolisme , ARN long non codant/métabolisme
19.
Cells ; 9(4)2020 04 16.
Article de Anglais | MEDLINE | ID: mdl-32316163

RÉSUMÉ

Zika virus (ZIKV) is an emergent arthropod-borne virus whose outbreak in Brazil has brought major public health problems. Infected individuals have different symptoms, including rash and pruritus, which can be relieved by the administration of antiallergics. In the case of pregnant women, ZIKV can cross the placenta and infect the fetus leading to congenital defects. We have identified that mast cells in the placentae of patients who had Zika during pregnancy can be infected. This led to our investigation on the possible role of mast cells during a ZIKV infection, using the HMC-1 cell line. We analyzed their permissiveness to infection, release of mediators and ultrastructural changes. Flow cytometry detection of ZIKV-NS1 expression 24 h post infection in 45.3% of cells showed that HMC-1 cells are permissive to ZIKV infection. Following infection, ß-hexosaminidase was measured in the supernatant of the cells with a notable release at 30 min. In addition, an increase in TNF-α, IL-6, IL-10 and VEGF levels were measured at 6 h and 24 h post infection. Lastly, different intracellular changes were observed in an ultrastructural analysis of infected cells. Our findings suggest that mast cells may represent an important source of mediators that can activate other immune cell types during a ZIKV infection, which has the potential to be a major contributor in the spread of the virus in cases of vertical transmission.


Sujet(s)
Cytokines/métabolisme , Mastocytes/immunologie , Infection par le virus Zika/immunologie , Virus Zika/immunologie , Adulte , Brésil , Lignée cellulaire , Femelle , Humains , Immunohistochimie , Transmission verticale de maladie infectieuse , Interleukine-10/métabolisme , Interleukine-6/métabolisme , Mastocytes/anatomopathologie , Mastocytes/ultrastructure , Mastocytes/virologie , Microscopie électronique à transmission , Placenta/immunologie , Placenta/métabolisme , Placenta/virologie , Grossesse , Facteur de nécrose tumorale alpha/métabolisme , Facteur de croissance endothéliale vasculaire de type A/métabolisme , Virus Zika/pathogénicité , Infection par le virus Zika/enzymologie , Infection par le virus Zika/physiopathologie , Infection par le virus Zika/transmission , beta-N-Acetylhexosaminidases/métabolisme
20.
FASEB J ; 34(2): 2749-2764, 2020 02.
Article de Anglais | MEDLINE | ID: mdl-31908042

RÉSUMÉ

Streptococcus pneumoniae is a major cause of community-acquired pneumonia leading to high mortality rates. Inflammation triggered by pneumococcal infection is necessary for bacterial clearance but must be spatially and temporally regulated to prevent further tissue damage and bacterial dissemination. Annexin A1 (AnxA1) mainly acts through Formyl Peptide Receptor 2 (FPR2) inducing the resolution of inflammation. Here, we have evaluated the role of AnxA1 and FPR2 during pneumococcal pneumonia in mice. For that, AnxA1, Fpr2/3 knockout (KO) mice and wild-type (WT) controls were infected intranasally with S pneumoniae. AnxA1 and Fpr2/3 KO mice were highly susceptible to infection, displaying uncontrolled inflammation, increased bacterial dissemination, and pulmonary dysfunction compared to WT animals. Mechanistically, the absence of AnxA1 resulted in the loss of lung barrier integrity and increased neutrophil activation upon S pneumoniae stimulation. Importantly, treatment of WT or AnxA1 KO-infected mice with Ac2-26 decreased inflammation, lung damage, and bacterial burden in the airways by increasing macrophage phagocytosis. Conversely, Ac2-26 peptide was ineffective to afford protection in Fpr2/3 KO mice during infection. Altogether, these findings show that AnxA1, via FPR2, controls inflammation and bacterial dissemination during pneumococcal pneumonia by promoting host defenses, suggesting AnxA1-based peptides as a novel therapeutic strategy to control pneumococcal pneumonia.


Sujet(s)
Annexine A1/métabolisme , Inflammation/métabolisme , Macrophages/métabolisme , Granulocytes neutrophiles/métabolisme , Pneumonie à pneumocoques/métabolisme , Récepteurs aux peptides formylés/métabolisme , Animaux , Modèles animaux de maladie humaine , Mâle , Souris de lignée BALB C , Souris de lignée C57BL , Phagocytose/effets des médicaments et des substances chimiques , Récepteurs de la lipoxine/métabolisme , Streptococcus pneumoniae/métabolisme
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