RESUMO
Fungal phytopathogens can suppress plant immune mechanisms in order to colonize living host cells. Identifying all the molecular components involved is critical for elaborating a detailed systems-level model of plant infection probing pathogen weaknesses; yet, the hierarchy of molecular events controlling fungal responses to the plant cell is not clear. Here we show how, in the blast fungus Magnaporthe oryzae, terminating rice innate immunity requires a dynamic network of redox-responsive E3 ubiquitin ligases targeting fungal sirtuin 2 (Sir2), an antioxidation regulator required for suppressing the host oxidative burst. Immunoblotting, immunopurification, mass spectrometry and gene functional analyses showed that Sir2 levels responded to oxidative stress via a mechanism involving ubiquitination and three antagonistic E3 ubiquitin ligases: Grr1 and Ptr1 maintained basal Sir2 levels in the absence of oxidative stress; Upl3 facilitated Sir2 accumulation in response to oxidative stress. Grr1 and Upl3 interacted directly with Sir2 in a manner that decreased and scaled with oxidative stress, respectively. Deleting UPL3 depleted Sir2 during growth in rice cells, triggering host immunity and preventing infection. Overexpressing SIR2 in the Δupl3 mutant remediated pathogenicity. Our work reveals how redox-responsive E3 ubiquitin ligases in M. oryzae mediate Sir2 accumulation-dependent antioxidation to modulate plant innate immunity and host susceptibility.
Assuntos
Magnaporthe , Oryza , Sirtuínas , Ascomicetos , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Imunidade Inata , Magnaporthe/metabolismo , Oryza/metabolismo , Oxirredução , Doenças das Plantas , Imunidade Vegetal , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Fungal interactions with plants can involve specific morphogenetic developments to access host cells, the suppression of plant defenses, and the establishment of a feeding lifestyle that nourishes the colonizer often-but not always-at the expense of the host. Reactive oxygen species (ROS) metabolism is central to the infection process, and the stage-specific production and/or neutralization of ROS is critical to the success of the colonization process. ROS metabolism during infection is dynamic-sometimes seemingly contradictory-and involves endogenous and exogenous sources. Yet, intriguingly, molecular decision-making involved in the spatio-temporal control of ROS metabolism is largely unknown. When also considering that ROS demands are similar between pathogenic and beneficial fungal-plant interactions despite the different outcomes, the intention of our review is to synthesize what is known about ROS metabolism and highlight knowledge gaps that could be hindering the discovery of novel means to mediate beneficial plant-microbe interactions at the expense of harmful plant-microbe interactions.
Assuntos
Fungos/metabolismo , Doenças das Plantas/microbiologia , Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
OBJECTIVES: We designed a written Canadian Anaphylaxis Action Plan for Kids (Kids' CAP) which incorporates validated pictograms with written instructions. Using a patient-centered approach, we aimed to validate the Kids' CAP and assess its impact on anaphylaxis recognition and treatment, and to determine its' perceived usefulness. PATIENT INVOLVEMENT: Children and their parents were involved in appraising the design and written contents of the Kids' CAP. METHODS: The design process consisted of a development phase and clinical validation phase. First, we assessed the readability and understandability of the Kids' CAP using validated instruments. Then, patients (12-17 years of age) and parents of patients (<12 years of age) were given the Kids' CAP during the first consultation with allergy specialists or an Emergency Department visit for anaphylaxis. Subsequently, we conducted a phone interview 2-3 weeks later to assess their comprehension of anaphylaxis management. We also used the Consumer Information Rating Form to measure the participants' perception of the design quality and usefulness of the Kids' CAP. RESULTS: Of the 230 participants enrolled, 205 (89%) completed the follow-up interview. The written contents of the Kid's CAP were modified to match grade 7 readability level. The total mean score of the Consumer Information Rating Form for comprehensibility was 23.1 (SD 2.4), and 25.1 (SD 2.3) for design quality. The mean comprehension score was 11.3 (SD 1.8) (reference range 0-12), with no significant difference between participants with and without previous experience with anaphylaxis, or high vs. low literacy level. CONCLUSION: Engaging children and parents in the design and contents of written anaphylaxis action plan is an innovative approach to produce a useful document for the end-users. PRACTICE IMPLICATIONS: The Kids' CAP is a valid tool that can be used in emergency departments and allergy clinics to improve patient's comprehension of anaphylaxis manifestations and treatment.
Assuntos
Anafilaxia , Anafilaxia/terapia , Canadá , Criança , Compreensão , Humanos , PaisRESUMO
OBJECTIVE: To review the diagnostic criteria for, the prevalence of, and the effectiveness of frenotomy for treatment of ankyloglossia. DATA SOURCES: MEDLINE and CINAHL databases were searched for articles suitable for a methodologic review of studies on various aspects of ankyloglossia. STUDY SELECTION: Studies that presented data on patients and addressed ankyloglossia in relation to breastfeeding were selected. Case reports, case series, retrospective studies, prospective controlled studies, and randomized controlled trials were included in the analysis. Opinion pieces, literature reviews, studies without data on patients, studies that did not focus on breastfeeding, position statements, and surveys were excluded. SYNTHESIS: There is no well-validated clinical method for establishing a diagnosis of ankyloglossia. Five studies using different diagnostic criteria found a prevalence of ankyloglossia of between 4% and 10%. The results of 6 non-randomized studies and 1 randomized study assessing the effectiveness of frenotomy for improving nipple pain, sucking, latch, and continuation of breastfeeding all suggested frenotomy was beneficial. No serious adverse events were reported. CONCLUSION: Diagnostic criteria for ankyloglossia are needed to allow for comparative studies of treatment. Frenotomy is likely an effective treatment, but further randomized controlled trials are needed to confirm this. A reliable frenotomy decision rule is also needed.
Assuntos
Freio Lingual/anormalidades , Doenças da Língua/diagnóstico , Doenças da Língua/terapia , Aleitamento Materno , Humanos , Lactente , Recém-Nascido , Freio Lingual/cirurgia , Prevalência , Comportamento de Sucção , Doenças da Língua/epidemiologia , Resultado do Tratamento , Reino Unido/epidemiologia , Estados Unidos/epidemiologiaRESUMO
Concentrations of carbon dioxide (CO(2)) are increasing in the atmosphere, affecting soybean (Glycine max L.) phytohormone signaling and herbivore resistance. Whether the impact of elevated CO(2) on phytohormones and induced defenses is a generalized response within this species is an open question. We examined jasmonic acid (JA) and salicylic acid (SA) under ambient and elevated CO(2) concentrations with and without Japanese beetle (Popillia japonica Newman) damage and artificial damage across six soybean cultivars (HS93-4118, Pana, IA 3010, Loda, LN97-15076, and Dwight). Elevated CO(2) reduced constitutive levels of JA and related transcripts in some but not all soybean cultivars. In contrast to the variation in JA, constitutive levels of salicylic were increased universally among soybean cultivars grown under elevated CO(2). Variation in hormonal signaling may underpin observed variation in the response of insect herbivores and pathogens to plants grown under elevated CO(2).
Assuntos
Dióxido de Carbono/farmacologia , Besouros/fisiologia , Glycine max/efeitos dos fármacos , Ácido Salicílico/metabolismo , Animais , Mudança Climática , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Herbivoria , Cinética , Oxilipinas/metabolismo , Transdução de Sinais , Glycine max/genética , Glycine max/metabolismoAssuntos
Fatores Etários , Anafilaxia/epidemiologia , Hipersensibilidade Alimentar/epidemiologia , Alérgenos/imunologia , Canadá/epidemiologia , Criança , Pré-Escolar , Exposição Ambiental , Epinefrina/administração & dosagem , Feminino , Humanos , Imunoglobulina E/metabolismo , Incidência , Lactente , Masculino , Fatores de Risco , Sesamum/imunologiaAssuntos
Abscesso Encefálico , Infecções do Sistema Nervoso Central , Colesteatoma da Orelha Média , Adulto , Abscesso Encefálico/patologia , Abscesso Encefálico/fisiopatologia , Infecções do Sistema Nervoso Central/patologia , Infecções do Sistema Nervoso Central/fisiopatologia , Colesteatoma da Orelha Média/patologia , Colesteatoma da Orelha Média/fisiopatologia , Diagnóstico Diferencial , Feminino , Humanos , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: There is considerable interest in using continuous venovenous hemofiltration machines for plasma exchange therapy in children. METHODS: Retrospective study of 7 patients and 61 plasma exchange treatments using the Baxter/Edwards Lifesciences BM25 machine with commercially available plasma filters (mostly Asahi Plasmaflo). RESULTS: The average total exchange volume was 1.5 times the plasma volume, achieved at a blood flow rate of 100 ml/m(2) (3.5 ml/kg/min) and a turnover rate of 25 ml/kg/h over a 3-hour duration. Fifty-six percent of the time, a mean heparin bolus of 29 units/kg resulted in subtherapeutic activated clotting times. Mean heparin infusion rates of 35 units of heparin/kg/h achieved effective anticoagulation. A calcium infusion rate of 0.11 +/- 0.05 mmol/kg/h avoided hypocalcemia. One patient experienced the serious complication of membrane reaction. CONCLUSIONS: This setup provides a safe approach to plasma exchange in children. A similar method could be implemented in other centers.