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Virtual culinary medicine education interventions have the potential to improve dietary behaviors, nutrition knowledge, cooking skills, and health outcomes for ethnically diverse individuals with type 2 diabetes. The purpose of this study is to describe the adaptation of the Nourishing the Community through Culinary Medicine (NCCM) program for virtual delivery, and the protocol for pilot testing this intervention. The intervention includes five 90-min virtual NCCM sessions streamed live from a Teaching Kitchen. Feasibility outcomes are recruitment, retention, acceptability, and satisfaction. Short-term effectiveness outcomes are measured through self-administered questionnaires, including perceived health, average daily servings of fruits and vegetables, frequency of healthy food consumption, shopping, cooking, and eating behaviors, cooking self-efficacy, diabetes self-management, perceived barriers to healthy eating, and nutrition knowledge. Demographics and biometric outcomes are sourced from the patient's electronic medical records including glycosylated hemoglobin (HbA1c), Body Mass Index, and blood pressure. We will conduct a single-arm pilot study to test the feasibility and short-term effectiveness of NCCM program with individuals with type 2 diabetes.
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This work examined the potential benefit of curcumin in breast cancer patients as a supplementary drug in ER-positive cancers. The results indicated that in the MCF-7 human breast cancer cell line, E2 and curcumin decreased cell proliferation and the colony-forming capacity and down-regulated protein expression as well as important molecules associated with cell proliferation, such as PCNA and estrogen receptor alpha; genes associated with the epithelial-mesenchymal transition, such as ß-catenin, Vimentin, and E-cadherin; and molecules associated with apoptosis. Clinical studies in bioinformatics have indicated a positive correlation between ESR1 and either CCND1 or BCL2 gene expression in all breast cancer patients. Thus, curcumin could become a potential natural adjuvant treatment for patients with estrogen receptor alpha-positive breast cancer and those with resistance or a poor response to endocrine therapy since the reactivation of estrogen receptor alpha is inevitable.
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According to self-determination theory, the need for competence, autonomy, and relatedness has been associated with intrinsic motivation. Fulfilling basic psychological needs can lead to better learning, academic performance, and well-being. In this study, an anatomy program integrated gamification and drawing methods to explore their influence on basic psychological needs satisfaction and potential learning implications. Basic psychological needs outcomes of sport sciences students were compared to test the effects of the Observe-Reflect-Draw-Edit-Repeat (ORDER) method and gamification (experimental condition) versus a non-ORDER and non-gamified program (control condition). These two different 30-h (7-week) anatomy education programs were implemented at two Spanish public universities with 116 first-year sport sciences students. Pre and post-treatment measurements were collected using the Basic Psychological Needs Satisfaction Scale. Statistical analyses included independent samples t-tests, ANCOVAs, and factorial repeated measures ANOVAs 2 × 2 (time × treatment). The gamified ORDER program achieved higher satisfaction scores in basic psychological needs compared to the control group (t = 2.98, p = 0.004, d = 0.54). Additionally, an interaction effect between time and treatment was observed (p = 0.042, η p 2 = 0.038). Treatment and interaction effects were observed for 'autonomy' (p = 0.003, η p 2 = 0.074) and 'competence' satisfaction (p = 0.048, η p 2 = 0.035). A time effect was found for 'relatedness' in the control group, but no significant treatment or interaction effects were identified. The causes of these effects are debated in the study, as well as the limitations. These findings support the notion that students' basic psychological needs are better satisfied in anatomy education with the implementation of this multimethod educational intervention based on ORDER and gamification.
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Anatomía , Gamificación , Humanos , Anatomía/educación , Aprendizaje , Estudiantes/psicología , Satisfacción PersonalRESUMEN
Science diplomacy is a fast-growing field of research, policy, and practice dedicated to understanding and reinforcing the connections between science and international affairs to tackle national, regional, and global issues. By aligning science and diplomacy, countries can attract talent, strengthen their national research ecosystems, provide avenues for participation of scientists in policy, and coordinate integrated solutions to challenges with technical dimensions. While Latin America has a long tradition of bilateral and regional cooperation, science still plays a marginal role in foreign policy, as has become evidenced by the response to the COVID-19 pandemic. With few exceptions, Latin American nations have a relatively immature science, technology, and innovation ecosystem, compounded by low public and private investments in research, coexisting with profound socio-economic inequalities, and large vulnerable populations. Such challenging conditions have created barriers to a fluid relationship between science and diplomacy, fundamentally characterized by inefficient communication between scientists and policymakers, weak collaboration channels, and duplicated roles, which altogether perpetuate siloed mentalities and a lack of trust between the two communities. Over the last decade, a first influential wave of Latin American scientists, diplomats, and other professionals, including five of the co-authors, have undertaken science diplomacy training provided by specialized organizations. Through these experiences, we recognized the need to elevate awareness and build capacities in science diplomacy in our respective countries and overall, across Latin America. Here, we describe emerging efforts and mechanisms to bridge the gap between scientists and policymakers at the national and regional level. Furthermore, we offer recommendations to amplify the impact of those pioneering initiatives toward consolidating a robust science diplomacy practice across the region. The national experiences described from Costa Rica, Mexico, and Panama can serve as a roadmap for other Latin American nations in the early process of developing a science diplomacy strategy, so they can also align themselves to a collective pathway. Most critically, we propose a way forward so that Latin America can leapfrog beyond disjointed training of individuals into integrated institutional strategies that can harness the tools of science diplomacy to enhance science-informed multilateral cooperation and enable more effective science-informed policymaking.
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This study analyzed the efficacy of autologous platelet-rich fibrin (PRF) in maintaining and recovering cell viability of the periodontal ligament (PDL). The PDL cells were isolated from 45 extracted teeth randomly distributed among 6 groups: 5 min, 1 h, 2 h, PRF 30 min, PRF 1 h and PRF 2 h. In the groups 5 min, 1 h and 2 h (n = 5), the teeth were kept dry in extra-alveolar times of 5 min, 1 h and 2 h respectively. The teeth of the groups PRF 30 min, PRF 1 h and PRF 2 h (n = 10) were kept dry at extra-alveolar times of 30 min, 1 and 2 h followed by immersion in PRF for 45 min. PDL cells were isolated by enzymatic digestion with type II collagenase and dispase, counted and analyzed for viability with Trypan blue vital dye in Neubauer chamber. The variables total number of cells and cell viability demonstrated that in the 5 min, 1 h and 2 h groups there was a decrease after the extra-alveolar dry times of 1 and 2 h. In comparison with the total number of cells, group 1 h, considered immediate reimplantation, did not present statistical difference when compared to the groups PRF 30 min, PRF 1 h and 2 h, a result that demonstrates that PRF assists in cell maintenance and recovery. PRF provided increased cell viability in relation to the different dry extra-alveolar times analyzed (p < 0.001). Autologous PRF presented effectiveness in maintaining and recovering PDL cells from extracted teeth and kept dry for up to 2 h.
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Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Fibrina Rica en Plaquetas/metabolismo , Supervivencia Celular/fisiología , Células Cultivadas , Colagenasas/metabolismo , Endopeptidasas/metabolismo , Humanos , Microscopía , Soluciones Preservantes de ÓrganosRESUMEN
BACKGROUND: Y-site administration of total parenteral nutrition (TPN) and drugs is frequently required in the intensive care setting. Amiodarone is commonly administered by continuous intravenous infusion and subject to be co-administered via a Y-site with TPN. The aim of this study is to determine the physicochemical stability of amiodarone Y-site administered with TPN. METHODS: Two standard TPN and 2 amiodarone solutions were designed. The 2 TPN differed in the lipid source (Lipofundin MCT/LCT® 20% or SMOFlipid® 20%). The 2 amiodarone solutions were prepared at different concentrations (900 mg and 1200 mg in 250 mL of dextrose 5% in water). Each TPN and amiodarone solutions ran at a rate that simulated a 24-hour Y-site infusion to obtain different admixture samples. Each sample was then visually examined and further tested to determine the mean lipid droplet size distribution by dynamic light scattering and amiodarone concentrations by HPLC. RESULTS: No alterations were detected by visual inspection. Average droplet size remained below 500 nm (252.5 ± 5.9 nm for Lipofundin MCT/LCT® TPN and 327.7 ± 14.4 nm for SMOFlipid® TPN). For the samples obtained after running 900 mg and 1200 mg amiodarone solutions with TPN, the concentrations observed at 24 hours were 0.4491 ± 0.0111 mg/mL and 0.5773 ± 0.0214 mg/mL, respectively. These results represent approximately 100% of the zero-time concentrations and are within ±15% of the predicted values. No degradation products were observed in the chromatograms. CONCLUSION: Amiodarone is physicochemically compatible with standard TPN via a Y-site administration at the tested amiodarone concentrations.
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Amiodarona/química , Antiarrítmicos/química , Fenómenos Químicos , Nutrición Parenteral Total , Interacciones Alimento-Droga/fisiologíaRESUMEN
A novel group of aryl methyl sulfones based on nonsteroidal anti-inflammatory compounds exhibiting a methyl sulfone instead of the acetic or propionic acid group was designed, synthesized and evaluated in vitro for inhibition against the human cyclooxygenase of COX-1 and COX-2 isoenzymes and in vivo for anti-inflammatory activity using the carrageenan induced rat paw edema model in rats. Also, in vitro chemosensitivity and in vivo analgesic and intestinal side effects were determined for defining the therapeutic and safety profile. Molecular modeling assisted the design of compounds and the interpretation of the experimental results. Biological assay results showed that methyl sulfone compounds 2 and 7 were the most potent COX inhibitors of this series and best than the corresponding carboxylic acids (methyl sulfone 2: IC50 COX-1â¯=â¯0.04 and COX-2â¯=â¯0.10⯵M, and naproxen: IC50 COX-1â¯=â¯11.3 and COX-2â¯=â¯3.36⯵M). Interestingly, the inhibitory activity of compound 2 represents a significant improvement compared to that of the parent carboxylic compound, naproxen. Further support to the results were gained by the docking studies which suggested the ability of compound 2 and 7 to bind into COX enzyme with low binding free energies. The improvement of the activity of some sulfones compared to the carboxylic analogues would be performed through a change of the binding mode or mechanism compared to the standard binding mode displayed by ibuprofen, as disclosed by molecular modeling studies. So, this study paves the way for further attention in investigating the participation of these new compounds in the pain inhibitory mechanisms. The most promising compounds 2 and 7 possess a therapeutical profile that enables their chemical scaffolds to be utilized for development of new NSAIDs.
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Antiinflamatorios no Esteroideos/farmacología , Antiulcerosos/farmacología , Dimetilsulfóxido/farmacología , Edema/tratamiento farmacológico , Úlcera Gástrica/tratamiento farmacológico , Sulfonas/farmacología , Ácido Acético , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antiulcerosos/síntesis química , Antiulcerosos/química , Carragenina , Dimetilsulfóxido/síntesis química , Dimetilsulfóxido/química , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Humanos , Masculino , Ratones , Modelos Moleculares , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Sulfonas/síntesis química , Sulfonas/química , TermodinámicaRESUMEN
INTRODUCTION: Bronchopulmonary dysplasia (BPD) is common in premature babies. It is difficult to predict the risk of developing this disease and its definition is not well characterized in high altitude cities. OBJECTIVE: To determine the operating characteristics of a BPD predictive scale for in preterm infants based on a classical BPD definition and one adjusted for altitude. MATERIALS AND METHOD: Observational, analytical, longitudinal study with infants gestational age ≤32 weeks admitted at two University Hospital's in the city of Bogotá, Colombia between June 2010 and December 2016. The 2001 NIH consensus definition for BPD was used and a definition with an altitude adjustment. Perinatal data, and the Romagnoli scale variables for the 3rd and 5th days were described. Score operational characteristics in relation to BPD frequency are measured using the two definitions. RESULTS: 335 patients were included. The median birth weight was 1335â¯g and GA was 31 weeks. For the BPD classical definition, the incidence was 85%, whereas after adjusting for altitude it was 20%. The scale score showed good overall discrimination (ROC curve, AUC 0.81-0.86). The sensitivity for the classical definition with a high cut point of 4 was between 93-98% and the adjusted for altitude was 28-37%. The specificity for the same cut was 28-32% with the classical definition and 96% with the adjusted one. CONCLUSIONS: The scale using the classical definition has high sensitivity, but it is not specific; adjusting the definition for altitude decreases sensitivity but increases specificity. New cutoffs points are needed on the scale or a change in the weight for the variables included in the model in order to be used in our high-altitude population.
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Altitud , Displasia Broncopulmonar/diagnóstico , Peso al Nacer , Displasia Broncopulmonar/etiología , Femenino , Edad Gestacional , Humanos , Incidencia , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Estudios Longitudinales , Masculino , Embarazo , Curva ROC , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: The objective of the present study was to test the effectiveness of financial incentives and traffic-light labels to reduce purchases of sugar-sweetened beverages in a community supermarket. DESIGN: In this randomized controlled trial, after a 2-month baseline period (February-March 2014), in-store traffic-light labels were posted to indicate healthy (green), less healthy (yellow) or unhealthy (red) beverages. During the subsequent five months (April-August 2014), participants in the intervention arm were eligible to earn a $US 25 in-store gift card each month they refrained from purchasing red-labelled beverages. SETTING: Urban supermarket in Chelsea, MA, USA, a low-income Latino community. SUBJECTS: Participants were customers of this supermarket who had at least one child living at home. A total of 148 customers (n 77 in the intervention group and n 71 in the control group) were included in the final analyses. RESULTS: Outcomes were monthly in-store purchases tracked using a store loyalty card and self-reported consumption of red-labelled beverages. Compared with control participants, the proportion of intervention participants who purchased any red-labelled beverages decreased by 9 % more per month (P=0·002). More intervention than control participants reduced their consumption of red-labelled beverages (-23 % v. -2 % for consuming ≥1 red beverage/week, P=0·01). CONCLUSIONS: Overall, financial incentives paired with in-store traffic-light labels modestly reduced purchase and consumption of sugar-sweetened beverages by customers of a community supermarket.
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Bebidas/estadística & datos numéricos , Dieta , Etiquetado de Alimentos/estadística & datos numéricos , Promoción de la Salud/métodos , Hispánicos o Latinos , Adolescente , Adulto , Dieta/economía , Dieta/estadística & datos numéricos , Encuestas sobre Dietas , Femenino , Hispánicos o Latinos/psicología , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Factores Socioeconómicos , Edulcorantes , Adulto JovenRESUMEN
The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia effector proteins and their contribution to Yersinia pathogenesis.
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The serine/threonine protein kinase YpkA is an essential virulence factor produced by pathogenic Yersinia species. YpkA is delivered into host mammalian cells via a type III secretion system and localizes to the inner side of the plasma membrane. We have previously shown that YpkA binds to and phosphorylates the α subunit of the heterotrimeric G protein complex, Gαq, resulting in inhibition of Gαq signaling. To identify residues in YpkA involved in substrate binding activity we generated GFP-YpkA N-terminal deletion mutants and performed coimmunoprecipitation experiments. We located a substrate-binding domain on amino acids 40-49 of YpkA, which lies within the previously identified membrane localization domain on YpkA. Deletion of amino acids 40-49 on YpkA interfered with substrate binding, substrate phosphorylation and substrate inhibition. Autophosphorylation regulates the kinase activity of YpkA. To dissect the mechanism by which YpkA transmits signals, we performed nano liquid chromatography coupled to tandem mass spectrometry to map in vivo phosphorylation sites. Multiple serine phosphorylation sites were identified in the secretion/translocation region, kinase domain, and C-terminal region of YpkA. Using site-directed mutagenesis we generated multiple YpkA constructs harboring specific serine to alanine point mutations. Our results demonstrate that multiple autophosphorylation sites within the N terminus regulate YpkA kinase activation, whereas mutation of serine to alanine within the C terminus of YpkA had no effect on kinase activity. YpkA autophosphorylation on multiple sites may be a strategy used by pathogenic Yersinia to prevent inactivation of this important virulence protein by host proteins.
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Proteínas Bacterianas/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , Yersinia enterocolitica/enzimología , Proteínas Bacterianas/química , Dominio Catalítico , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Células HEK293 , Interacciones Huésped-Patógeno , Humanos , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas/química , Transducción de SeñalAsunto(s)
Proteínas Bacterianas/farmacología , Toxinas Bacterianas/farmacología , Endotoxinas/farmacología , Proteínas Hemolisinas/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Viabilidad Microbiana/inmunología , Amicacina/farmacología , Antibacterianos/farmacología , Toxinas de Bacillus thuringiensis , Células Cultivadas/efectos de los fármacos , Células Cultivadas/inmunología , Concanavalina A/farmacología , Evaluación Preclínica de Medicamentos , Humanos , Leucocitos Mononucleares/inmunología , Viabilidad Microbiana/efectos de los fármacos , Proteus mirabilis/efectos de los fármacos , Proteus mirabilis/crecimiento & desarrollo , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Proteínas Recombinantes/farmacología , Salmonella/efectos de los fármacos , Salmonella/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
Pathogenic bacteria of the genus Yersinia employ a type III secretion system to inject bacterial effector proteins directly into the host cytosol. One of these effectors, the Yersinia serine/threonine protein kinase YpkA, is an essential virulence determinant involved in host actin cytoskeletal rearrangements and in inhibition of phagocytosis. Here we report that YpkA inhibits multiple Galphaq signaling pathways. The kinase activity of YpkA is required for Galphaq inhibition. YpkA phosphorylates Ser47, a key residue located in the highly conserved diphosphate binding loop of the GTPase fold of Galphaq. YpkA-mediated phosphorylation of Ser47 impairs guanine nucleotide binding by Galphaq. Y. pseudotuberculosis expressing wild-type YpkA, but not a catalytically inactive YpkA mutant, interferes with Galphaq-mediated signaling pathways. Identification of a YpkA-mediated phosphorylation site in Galphaq sheds light on the contribution of the kinase activity of YpkA to Yersinia pathogenesis.
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Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/fisiología , Transducción de Señal/fisiología , Yersinia enterocolitica/fisiología , Yersinia pestis/fisiología , Actinas/fisiología , Proteínas Bacterianas/metabolismo , Línea Celular , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Humanos , Riñón , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Proteínas Recombinantes de Fusión/metabolismo , Estrés Mecánico , Transfección , Yersinia enterocolitica/enzimología , Yersinia pestis/enzimología , Proteína de Unión al GTP rhoA/metabolismoAsunto(s)
Humanos , Proteínas Bacterianas/farmacología , Toxinas Bacterianas/farmacología , Endotoxinas/farmacología , Proteínas Hemolisinas/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Viabilidad Microbiana/inmunología , Amicacina/farmacología , Antibacterianos/farmacología , Células Cultivadas/efectos de los fármacos , Células Cultivadas/inmunología , Concanavalina A/farmacología , Evaluación Preclínica de Medicamentos , Leucocitos Mononucleares/inmunología , Viabilidad Microbiana/efectos de los fármacos , Proteus mirabilis/efectos de los fármacos , Proteus mirabilis/crecimiento & desarrollo , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Proteínas Recombinantes/farmacología , Salmonella/efectos de los fármacos , Salmonella/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
The invasion strategies used by Yersinia species involve the 'hijacking' of host cellular signaling pathways, often involving microbial gene products that mimic the functions of the cellular proteins. Yersinia uses a type III secretion system to inject these microbial gene products, referred to as Yersinia effector proteins, into the host cytosol. Yersinia effector proteins can inhibit the host immune system through a diverse array of mechanisms including inhibition of the inflammatory response by interfering with cytokine production, inhibition of phagocytosis by disrupting the actin cytoskeleton, induction of apoptosis in macrophages and through the formation of novel signaling complexes.
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Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/metabolismo , Sistema Inmunológico/efectos de los fármacos , Yersinia/patogenicidad , Proteínas de la Membrana Bacteriana Externa/farmacología , Proteínas Bacterianas/farmacología , Citosol/metabolismo , Humanos , Fagocitosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Yersinia/crecimiento & desarrolloRESUMEN
Interferon regulatory factor 3 (IRF3) mediates the transcriptional induction of interferon-stimulated genes (ISGs) in response to viral and bacterial infections. Here we show that the hydroxystilbene piceatannol inhibits the LPS-mediated activation of IRF3 and subsequent ISG induction. Consequently, piceatannol blocks the LPS-induced up-regulation of critical mediators of the inflammatory response such as interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), intercellular adhesion molecule 1 (ICAM-1), and macrophage chemoattractant protein (MCP-1). Furthermore, the LPS-mediated induction of tissue factor (TF), a cell surface protein responsible for initiating the coagulation cascade, is also inhibited by piceatannol. The effectiveness of piceatannol in blocking both the inflammatory response and the coagulation pathway is evidenced by its ability to confer protection against LPS-induced septic shock in a murine model. Thus, IRF3 appears to be a promising target for pharmacologic intervention in the prevention or treatment of septic shock syndrome.
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Proteínas de Unión al ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Lipopolisacáridos/metabolismo , Sepsis , Choque/patología , Estilbenos/farmacología , Factores de Transcripción/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Quimiocina CCL2/metabolismo , Proteínas de Unión al ADN/antagonistas & inhibidores , Ensayo de Inmunoadsorción Enzimática , Humanos , Inflamación , Molécula 1 de Adhesión Intercelular/metabolismo , Factor 3 Regulador del Interferón , Interferones/metabolismo , Interleucina-6/metabolismo , Ratones , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribonucleasas/metabolismo , Factores de Tiempo , Factores de Transcripción/antagonistas & inhibidores , Transcripción Genética , Transfección , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
IFN-regulatory factor 3 (IRF3) is known to participate in the transcriptional induction of chemokines and cytokines, including IFNs, as a result of viral or bacterial infection. In this study, we demonstrate that the LPS-mediated activation of IRF3 and subsequent induction of chemokine genes or IRF3-responsive reporter constructs are inhibited after exposure of human or murine macrophages to the Bacillus anthracis toxin lethal factor. The inhibitory effect is caused by interference with the activation of the stress-activated protein kinase, p38, due to a proteolytic cleavage of mitogen-activated protein kinase kinase 6, and can be overcome by the ectopic expression of a cleavage-resistant mutant of mitogen-activated protein kinase kinase 6 or a constitutively active IRF3. The lethal factor-mediated inhibition of IRF3 activation and subsequent cytokine production through bacterial membrane components offers Bacillus anthracis an efficient mechanism to evade the innate immune response.
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Antígenos Bacterianos , Bacillus anthracis/inmunología , Toxinas Bacterianas/farmacología , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/metabolismo , Lipopolisacáridos/farmacología , Subunidades de Proteína/farmacología , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Animales , Bacillus anthracis/patogenicidad , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Línea Celular Tumoral , Quimiocina CCL5/biosíntesis , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Humanos , Hidrólisis , Factor 3 Regulador del Interferón , Lipopolisacáridos/antagonistas & inhibidores , MAP Quinasa Quinasa 3 , MAP Quinasa Quinasa 6 , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/microbiología , Ratones , Ratones Noqueados , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/fisiología , Mutagénesis Sitio-Dirigida , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Factores de Transcripción/deficiencia , Factores de Transcripción/genética , Transcripción Genética/inmunología , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Viruses utilize numerous mechanisms to counteract the host's immune response. Interferon production is a major component of the host antiviral response. Many viruses, therefore, produce proteins or RNA molecules that inhibit interferon-induced signal transduction pathways and their associated antiviral effects. Surprisingly, some viruses directly induce expression of interferon-induced genes. SM, an early lytic Epstein-Barr virus (EBV) nuclear protein, was found to specifically increase the expression of several genes (interferon-stimulated genes) that are known to be strongly induced by alpha/beta interferons. SM does not directly stimulate alpha/beta interferon secretion but instead induces STAT1, an intermediate step in the interferon signaling pathway. SM is a posttranscriptional activator of gene expression and increases STAT1 mRNA accumulation, particularly that of the functionally distinct STAT1beta splice variant. SM expression in B lymphocytes is associated with decreased cell proliferation but does not decrease cell viability or induce cell cycle arrest. These results indicate that EBV can specifically induce cellular genes that are normally physiological targets of interferon by inducing components of cytokine signaling pathways. Our findings therefore suggest that some aspects of the interferon response may be positively modulated by infecting viruses.