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Plant innate immunity mediated by the nucleotide-binding leucine-rich repeat (NLR) class of immune receptors plays an important role in defense against various pathogens. Although key biochemical events involving NLR activation and signaling have been recently uncovered, we know very little about the transcriptional regulation of NLRs and their downstream signaling components. Here, we show that the Toll-Interleukin 1 receptor homology domain containing NLR (TNL) gene N (Necrosis), which confers resistance to Tobacco mosaic virus, is transcriptionally induced upon immune activation. We identified two conserved transcription factors, N required C3H zinc finger 1 (NRZ1) and N required MYB-like transcription factor 1 (NRM1), that activate N in an immune responsive manner. Genetic analyses indicated that NRZ1 and NRM1 positively regulate coiled-coil domain-containing NLR- and TNL-mediated immunity and function independently of the signaling component Enhanced Disease Susceptibility 1. Furthermore, NRZ1 functions upstream of NRM1 in cell death signaling, and their gene overexpression induces ectopic cell death and expression of NLR signaling components. Our findings uncovered a conserved transcriptional regulatory network that is central to NLR-mediated cell death and immune signaling in plants.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas NLR , Imunidade Vegetal , Fatores de Transcrição , Imunidade Vegetal/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas NLR/genética , Proteínas NLR/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais/genética , Doenças das Plantas/virologia , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Morte CelularRESUMO
Context: Preliminary studies have suggested that Mindful Self-Compassion (MSC) programs can reduce psychological problems, such as anxiety and depression, but they have rarely been investigated in people with cancer. Objective: The study intended to investigate the effects of a standard MSC program on psychological well-being and levels of compassion in people with breast cancer. Design: The study was an internal service evaluation that used a pre-post, quasi-experimental design. Setting: The study took place at Breast Cancer Haven, a national cancer-support charity, in London, UK. Participants: Of the 63 people who attended the courses, 38 completed the questionnaires both at baseline and postintervention (60%). Of the 49 participants who provided demographic details, 43 were living with breast cancer; one had bowel cancer; and five didn't have cancer. Of those 49 participants, 44 were females and 5 were males; 43% were aged 29-50 years and 57% were aged 51-69 years; and 73% were of European American/White ethnicity. Intervention: Participants took part in a standard MSC program exploring mindfulness and self-compassion for eight weeks, three hours each week, plus a four-hour retreat. Outcome Measures: At baseline and postintervention, participants completed four questionnaires measuring: (1) self-compassion-the Self-Compassion Scale - Short Form (SCS-SF), (2) satisfaction with life-the Satisfaction with Life Scale (SWLS), (3) stress and depression-Depression, Anxiety, and Stress Scale (DASS), and (4) mindfulness-Cognitive and Affective Mindfulness Scale-Revised (CAMS-R). They also completed a short feedback form about their course experiences. Results: The study found statistically significant increases in self-compassion (n = 37), with P < .001; satisfaction with life (n = 36), with P < .001; and mindfulness (n = 35), with P < .001, between baseline and postintervention as well as significant decreases in stress (n = 38), with P < .001, and depression (n = 36), with P < .001 (Wilcoxon signed rank test). Participants stated that while they had found the course to be challenging, they also had found new ways to be aware of and respond to their needs for kindness and self-compassion. They felt the course had changed their lives for the future. Conclusions: The findings support the beneficial effects of a standard MSC course on the psychological well-being of people with breast cancer. Further larger, more rigorous mixed-method studies are required to corroborate these preliminary findings.
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Neoplasias da Mama , Atenção Plena , Bem-Estar Psicológico , Autocompaixão , Neoplasias da Mama/psicologia , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , MasculinoRESUMO
Women who are pregnant and living with HIV have traditionally been excluded from clinical trials regarding new pharmacotherapy. Immediate initiation of antiretroviral therapy (ART) is recommended for women who are pregnant and living with HIV. Integrase inhibitors (INSTIs) are first-line recommended agents as they lead to more rapid HIV viral load reduction. We conducted a retrospective study of women who are pregnant and living with HIV who received prenatal care at the University of Washington. Mothers were categorized by ART class: INSTI, protease inhibitors (PI), and non-nucleoside reverse transcriptase inhibitors (NNRTI). Chi-square and t-tests were used for the analysis of baseline characteristics, and generalized estimating equations were used to adjust for HIV viral suppression between groups. There were a total of 234 mother-infant pairs whose pregnancies progressed beyond 20 weeks. The study demonstrated that women on INSTI regimens were more likely to have a shorter time to viral load suppression than women on NNRTI regimens. Additionally, seven congenital anomalies were identified in this cohort, none of which were neural tube defects. There was no perinatal transmission of HIV to any of the infants. This small cohort of women provides high-quality data regarding the safety and efficacy of INSTI use for both mothers and infants in resource-rich settings.
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Cucumber green mottle mosaic virus (CGMMV), as a typical seed-borne virus, causes costly and devastating diseases in the vegetable trade worldwide. Genetic sources for resistance to CGMMV in cucurbits are limited, and environmentally safe approaches for curbing the accumulation and spread of seed-transmitted viruses and cultivating completely resistant plants are needed. Here, we describe the design and application of RNA interference-based technologies, containing artificial microRNA (amiRNA) and synthetic trans-acting small interfering RNA (syn-tasiRNA), against conserved regions of different strains of the CGMMV genome. We used a rapid transient sensor system to identify effective anti-CGMMV amiRNAs. A virus seed transmission assay was developed, showing that the externally added polycistronic amiRNA and syn-tasiRNA can successfully block the accumulation of CGMMV in cucumber, but different virulent strains exhibited distinct influences on the expression of amiRNA due to the activity of the RNA-silencing suppressor. We also established stable transgenic cucumber plants expressing polycistronic amiRNA, which conferred disease resistance against CGMMV, and no sequence mutation was observed in CGMMV. This study demonstrates that RNA interference-based technologies can effectively prevent the occurrence and accumulation of CGMMV. The results provide a basis to establish and fine-tune approaches to prevent and treat seed-based transmission viral infections.
Assuntos
Cucumis sativus , Resistência à Doença/genética , MicroRNAs , Doenças das Plantas , Plantas Geneticamente Modificadas , RNA de Plantas , Tobamovirus , Cucumis sativus/genética , Cucumis sativus/metabolismo , Cucumis sativus/virologia , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/virologia , RNA de Plantas/genética , RNA de Plantas/metabolismo , Tobamovirus/genética , Tobamovirus/metabolismoRESUMO
Plant genomes encode large numbers of nucleotide-binding (NB) leucine-rich repeat (LRR) immune receptors (NLR) that mediate effector triggered immunity (ETI) and play key roles in protecting crops from diseases caused by devastating pathogens. Fitness costs are associated with plant NLR genes and regulation of NLR genes by micro(mi)RNAs and phased small interfering RNAs (phasiRNA) is proposed as a mechanism for reducing these fitness costs. However, whether NLR expression and NLR-mediated immunity are regulated during plant growth is unclear. We conducted genome-wide transcriptome analysis and showed that NLR expression gradually increased while expression of their regulatory small RNAs (sRNA) gradually decreased as plants matured, indicating that sRNAs could play a role in regulating NLR expression during plant growth. We further tested the role of miRNA in the growth regulation of NLRs using the tobacco mosaic virus (TMV) resistance gene N, which was targeted by miR6019 and miR6020. We showed that N-mediated resistance to TMV effectively restricted this virus to the infected leaves of 6-week old plants, whereas TMV infection was lethal in 1- and 3-week old seedlings due to virus-induced systemic necrosis. We further found that N transcript levels gradually increased while miR6019 levels gradually decreased during seedling maturation that occurs in the weeks after germination. Analyses of reporter genes in transgenic plants showed that growth regulation of N expression was post-transcriptionally mediated by MIR6019/6020 whereas MIR6019/6020 was regulated at the transcriptional level during plant growth. TMV infection of MIR6019/6020 transgenic plants indicated a key role for miR6019-triggered phasiRNA production for regulation of N-mediated immunity. Together our results demonstrate a mechanistic role for miRNAs in regulating innate immunity during plant growth.
Assuntos
Regulação da Expressão Gênica de Plantas , Imunidade Inata , Nicotiana/metabolismo , Imunidade Vegetal , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Solanum lycopersicum/metabolismo , Resistência à Doença , Perfilação da Expressão Gênica , Genes Reporter , Genoma de Planta , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/imunologia , Solanum lycopersicum/virologia , Proteínas NLR/genética , Proteínas NLR/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/imunologia , Folhas de Planta/metabolismo , Folhas de Planta/virologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/virologia , RNA de Plantas , Plântula/crescimento & desenvolvimento , Plântula/imunologia , Plântula/metabolismo , Plântula/virologia , Especificidade da Espécie , Nicotiana/crescimento & desenvolvimento , Nicotiana/imunologia , Nicotiana/virologia , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/crescimento & desenvolvimento , Vírus do Mosaico do Tabaco/fisiologiaRESUMO
INTRODUCTION: Sports-related concussions (SRCs) have received attention due to their prevalence in youth. An SRC results from a strong force causing neurological impairment. Recent research has recommended rehabilitation within the first week post-SRC after 24 to 48 hours of rest. The postacute phase is defined as 48 hours to 7 days post-SRC. It is imperative to evaluate the most effective mode and intensity of physical activity to reduce symptoms and improve outcomes. METHODS: CINAHL, PubMed, SPORTDiscus, and Web of Science databases were used to search the terms "brain concussion" AND "exercise" and variations of these terms. The evidence level for each study was evaluated using the 2011 Oxford Center for Evidence-Based Medicine Guide. The methodological rigor of each study was evaluated using a scale adapted from Medlicott and Harris. RESULTS: Two thousand sixty-eight records were identified. Six studies were included in this systematic review. Three studies were classified as moderately strong. The remaining 3 studies were considered weak. Five of the studies used either a cycle ergometer or a treadmill. The sixth study used walking, cycling, and swimming, as well as sports drills. All of these modes of exercise were determined to be safe. All studies utilized low- and moderate-intensity interventions, which were found to be nondetrimental and showed improved recovery time and symptom resolution. Five of the studies also incorporated components of high-intensity exercise that was also found to be nondetrimental, and they showed a positive influence on recovery time and symptom resolution. However, all activity in each of the reviewed studies started at a low level and progressed up to a higher level only as each individual client's symptoms permitted. DISCUSSION: Overall, this review found that various modes of activity at light-, moderate-, and high-intensity levels are efficacious and can be safely used during the postacute phase of SRC. CONCLUSION: Though the volume of literature at this time is limited, therapists should consider prescribing closely monitored individualized exercise programs utilizing progressive intensities when treating patients during the postacute phase of SRC.
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Traumatismos em Atletas/terapia , Concussão Encefálica/terapia , Terapia por Exercício/métodos , Exercício Físico , Humanos , DescansoRESUMO
MAIN CONCLUSION: We describe a Nicotiana benthamiana system for rapid identification of artificial microRNA (amiRNA) to control cucumber green mottle mosaic virus (CGMMV) disease. Although artificial miRNA technology has been used to control other viral diseases, it has not been applied to reduce severe cucumber green mottle mosaic virus (CGMMV) disease and crop loss in the economically important cucurbits. We used our system to identify three amiRNAs targeting CGMMV RNA (amiR1-CP, amiR4-MP and amiR6-Rep) and show that their expression reduces CGMMV replication and disease in virus-infected plants. This work streamlines the process of generating amiRNA virus-resistant crops and can be broadly applied to identify active antiviral amiRNAs against a broad spectrum of viruses to control disease in diverse crops.
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Cucumis sativus/genética , Resistência à Doença/genética , MicroRNAs/genética , Doenças das Plantas/imunologia , Tobamovirus/fisiologia , Cucumis sativus/imunologia , Cucumis sativus/virologia , Dano ao DNA , Doenças das Plantas/virologia , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/virologiaRESUMO
The concept that psoriasis is an autoimmune disease needs to be questioned. The autoimmune label has been based on molecular mimicry between streptococcal and keratin proteins and the existence of homologous peptides between these proteins. However, it is only peripheral blood CD8, and not CD4, T lymphocytes that respond to the homologous peptides. This ignores the fact that it is CD4 T cells which are necessary to initiate psoriasis. Recent studies on skin bacterial microbiota have found a variety of bacteria in both normal skin and psoriatic lesions. In biopsy specimens, the most common phylum was Firmicutes and the most common genus streptococcus in both psoriasis and normal skin. The innate immune system is activated in psoriasis, and recent genetic findings have shown the majority of susceptibility loci are associated with innate immunity. There is a known clinical relationship between both Crohn's disease (CD) and periodontitis, and psoriasis, and patients with psoriasis share mutations in some innate immunity genes with individuals with CD. It is now accepted that CD is due to a breakdown of immune tolerance (dysbiosis) to bacteria in the intestine. These findings suggest that psoriasis is initiated by an abnormal response to bacteria in the skin due to genetic factors.
Assuntos
Doenças Autoimunes/imunologia , Psoríase/imunologia , Doenças Autoimunes/etiologia , Doenças Autoimunes/microbiologia , Doença de Crohn/etiologia , Doença de Crohn/imunologia , Predisposição Genética para Doença , Humanos , Imunidade Inata/genética , Microbiota , Modelos Biológicos , Mimetismo Molecular/imunologia , Psoríase/etiologia , Pele/microbiologiaRESUMO
Plant genomes contain large numbers of cell surface leucine-rich repeat (LRR) and intracellular nucleotide binding (NB)-LRR immune receptors encoded by resistance (R) genes that recognize specific pathogen effectors and trigger resistance responses. The unregulated expression of NB-LRR genes can trigger autoimmunity in the absence of pathogen infection and inhibit plant growth. Despite the potential serious consequence on agricultural production, the mechanisms regulating R-gene expression are not well understood. We identified microRNA (miRNA) progenitor genes precursor transcripts, and two miRNAs [nta-miR6019 (22-nt) and nta-miR6020 (21-nt)] that guide cleavage of transcripts of the Toll and Interleukin-1 receptor-NB-LRR immune receptor N from tobacco that confers resistance to tobacco mosaic virus (TMV). We further showed that cleavage by nta-miR6019 triggers RNA-dependent RNA polymerase 6- and ribonuclease Dicer-like 4-dependent biogenesis of 21-nt secondary siRNAs "in phase" with the 22-nt miR6019 cleavage site. Furthermore, we found that processing of the 22-nt nta-miR6019 depended on an asymmetric bulge caused by mismatch in the nta-miR6019 precursor. Interestingly, coexpression of N with nta-miR6019 and nta-miR6020 resulted in attenuation of N-mediated resistance to TMV, indicating that these miRNAs have functional roles in NB-LRR regulation. Using a bioinformatics approach, we identified six additional 22-nt miRNA and two 21-nt miRNA families from three Solanaceae species-tobacco, tomato, and potato. We show that members of these miRNA families cleave transcripts of predicted functional R genes and trigger production of phased secondary 21-nt siRNAs. Our results demonstrate a conserved role for miRNAs and secondary siRNAs in NB-LRR/LRR immune receptor gene regulation and pathogen resistance in Solanaceae.
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Imunidade Inata , MicroRNAs/fisiologia , Nicotiana/fisiologia , Receptores Imunológicos/fisiologia , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Inativação Gênica , MicroRNAs/genética , Dados de Sequência Molecular , Receptores Imunológicos/genética , Homologia de Sequência do Ácido Nucleico , Nicotiana/imunologiaRESUMO
The crosstalk between clathrin-mediated endocytosis (CME) and the autophagy pathway has been reported in mammals; however, the interconnection of CME with autophagy has not been established in plants. Here, we report that the Arabidopsis CLATHRIN LIGHT CHAIN (CLC) subunit 2 and 3 double mutant, clc2-1 clc3-1, phenocopies Arabidopsis AUTOPHAGY-RELATED GENE (ATG) mutants in both autoimmunity and nutrient sensitivity. Accordingly, the autophagy pathway is significantly compromised in the clc2-1 clc3-1 mutant. Interestingly, multiple assays demonstrate that CLC2 directly interacts with ATG8h/ATG8i in a domain-specific manner. As expected, both GFP-ATG8h/GFP-ATG8i and CLC2-GFP are subjected to autophagic degradation, and degradation of GFP-ATG8h is significantly reduced in the clc2-1 clc3-1 mutant. Notably, simultaneous knockout of ATG8h and ATG8i by CRISPR-Cas9 results in enhanced resistance against Golovinomyces cichoracearum, supporting the functional relevance of the CLC2-ATG8h/8i interactions. In conclusion, our results reveal a link between the function of CLCs and the autophagy pathway in Arabidopsis.
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Proteínas de Arabidopsis , Arabidopsis , Autofagia , Cadeias Leves de Clatrina , Imunidade Vegetal , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/metabolismo , Cadeias Leves de Clatrina/metabolismo , Cadeias Leves de Clatrina/genética , Imunidade Vegetal/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genéticaRESUMO
Nicotiana tabacum and Nicotiana benthamiana are widely used models in plant biology research. However, genomic studies of these species have lagged. Here we report the chromosome-level reference genome assemblies for N. benthamiana and N. tabacum with an estimated 99.5% and 99.8% completeness, respectively. Sensitive transcription start and termination site sequencing methods were developed and used for accurate gene annotation in N. tabacum. Comparative analyses revealed evidence for the parental origins and chromosome structural changes, leading to hybrid genome formation of each species. Interestingly, the antiviral silencing genes RDR1, RDR6, DCL2, DCL3, and AGO2 were lost from one or both subgenomes in N. benthamiana, while both homeologs were kept in N. tabacum. Furthermore, the N. benthamiana genome encodes fewer immune receptors and signaling components than that of N. tabacum. These findings uncover possible reasons underlying the hypersusceptible nature of N. benthamiana. We developed the user-friendly Nicomics (http://lifenglab.hzau.edu.cn/Nicomics/) web server to facilitate better use of Nicotiana genomic resources as well as gene structure and expression analyses.
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Cromossomos , Nicotiana , Nicotiana/genética , Genes de Plantas , Genômica , Anotação de Sequência MolecularRESUMO
Plant microRNAs (miRNAs) and trans-acting small interfering RNAs (tasiRNAs) play important roles in a variety of biological processes. Bioinformatics prediction and small RNA (sRNA) cloning are the most important approaches for identification of miRNAs and tasiRNAs and their targets. However, these approaches are not readily accessible to every researcher. Here we present SoMART, a web server for miRNA/tasiRNA analysis resources and tools, which is designed for researchers who are interested in identifying miRNAs or tasiRNAs that potentially regulate genes of interest. The server includes four sets of tools: 'Slicer detector' for detecting sRNAs targeting input genes, 'dRNA mapper' for detecting degradome (d)RNA products derived from input genes, 'PreMIR detector' for identifying miRNA precursors (MIRs) or tasiRNA precursor (TASs) of input sRNAs, and 'sRNA mapper' for mapping sRNAs onto input genes. We also developed a dRNA-seq protocol to achieve longer dRNA reads for better characterization of miRNA precursors by dRNA mapper. To validate the server function and robustness, we installed sRNA, dRNA and collected genomic DNA or transcriptome databases from Arabidopsis and solanaceous plants, and characterized miR172-mediated regulation of the APETALA2 gene in potato (Solanum tuberosum) and demonstrated conservation of MIR390-triggered TAS3 in tomato (Solanum lycopersicum). More importantly, we predicted the existence of MIR482-triggered TAS5 in tomato. We further tested and confirmed the efficiency and accuracy of the server by analyses of 21 validated miRNA targets and 115 miRNA precursors in Arabidopsis thaliana. SoMART is available at http://somart.ist.berkeley.edu.
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Genes de Plantas , Internet , MicroRNAs/análise , RNA de Plantas/análise , Software , Arabidopsis/genética , Sequência de Bases , DNA de Plantas/análise , DNA de Plantas/genética , Bases de Dados Genéticas , Solanum lycopersicum/genética , MicroRNAs/genética , Dobramento de RNA , RNA de Plantas/genética , Sensibilidade e Especificidade , Alinhamento de Sequência , Análise de Sequência de RNA/métodosRESUMO
This article provides a detailed description of how to implement a ripple mapping activity to assess youth program effects on community capital and concludes with examples from Maine and Kansas. The maps lead to group reflection on project outcomes and further research and evaluation questions for group members. The results from five Maine communities showed that youth in schools and community clubs promoted intentional, mutually beneficial relationships with community groups and businesses and increased shared action on community projects. Likewise, youth in five small Kansas towns implemented and evaluated health promotion projects and found through mapping that youth built social capital in addition to awareness, knowledge, and skills in community health promotion. Ripple mapping helped to demonstrate that actions of youth-adult partnerships in both states improved the built, human, and social capital in small towns.
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Avaliação de Programas e Projetos de Saúde/normas , Mudança Social , Meio Social , Adolescente , Promoção da Saúde , Humanos , Kansas , Maine , Características de ResidênciaRESUMO
Understanding the efficacy of SARS-CoV-2 vaccination in people on immunosuppressive drugs, including those with rheumatoid arthritis (RA), is critical for their protection. Vaccine induced protection requires antibodies, CD4+ T cells, and CD8+ T cells, but it is unclear if these are equally affected by immunomodulatory drugs. Here, we determined how humoral and cellular SARS-CoV-2 vaccination responses differed between people with RA and controls, and which drug classes impacted these responses. Blood was collected from participants with RA on immunomodulatory drugs and controls after their second, third, and fourth SARS-CoV-2 vaccinations. Receptor binding domain (RBD)-specific antibodies were quantified by ELISA. Spike-specific memory T cells were quantitated using flow cytometry. Linear mixed models assessed the impact of age, sex, and immunomodulatory drug classes on SARS-CoV-2 vaccination responses. Compared to non-RA controls (n = 35), participants with RA on immunomodulatory drugs (n = 62) had lower anti-RBD IgG and spike-specific CD4+ T cell levels, but no deficits in spike-specific CD8+ T cells, following SARS-CoV-2 vaccination. Use of costimulation inhibitors was associated with lower humoral responses. JAK inhibitors were associated with fewer spike-specific CD4+ T cells. Participants with RA on immunomodulatory drugs mounted weaker responses to SARS-CoV-2 vaccination, with different drug classes impacting the cellular and humoral compartments.
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Artrite Reumatoide , COVID-19 , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , Linfócitos T CD8-Positivos , Vacinação , Anticorpos , Artrite Reumatoide/tratamento farmacológico , Agentes de Imunomodulação , Imunidade Celular , Anticorpos AntiviraisRESUMO
The plant hormone salicylic acid plays an important role in balancing plant immunity and growth. In this issue of Cell Host & Microbe, Liu et al. (2022) discovered that a long non-coding RNA, lncSABC1, promotes growth in uninfected plants and unleashes defenses when pathogens attack by transcriptionally regulating salicylic acid biosynthesis.
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RNA Longo não Codificante , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Reguladores de Crescimento de Plantas , Imunidade Vegetal , Plantas/genética , RNA Longo não Codificante/genética , Ácido SalicílicoRESUMO
The genomic perspective aids in integrating the analysis of single resistance (R-) genes into a higher order model of complex plant resistance systems. The majority of R-genes encode a class of proteins with nucleotide binding (NB) and leucine-rich repeat (LRR) domains. Several R-proteins act in multi-protein R-complexes that mediate interaction with pathogen effectors to induce resistance signaling. The complexity of these systems seems to have resulted from multiple rounds of plant-pathogen co-evolution. R-gene evolution is thought to be facilitated by the formation of R-gene clusters, which permit sequence exchanges via recombinatorial mispairing and generate high haplotypic diversity. This pattern of evolution may also generate diversity at other loci that contribute to the R-complex. The rate of recombination at R-clusters is not necessarily homogeneous or consistent over evolutionary time: recent evidence suggests that recombination at R-clusters is increased following pathogen infection, suggesting a mechanism that induces temporary genome instability in response to extreme stress. DNA methylation and chromatin modifications may allow this instability to be conditionally regulated and targeted to specific genome regions. Knowledge of natural R-gene evolution may contribute to strategies for artificial evolution of novel resistance specificities.
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Evolução Molecular , Genes de Plantas , Doenças das Plantas/genética , Plantas/genética , Montagem e Desmontagem da Cromatina , Evolução Molecular Direcionada , Genoma de Planta , Imunidade Inata/genética , Modelos Genéticos , Família Multigênica , Recombinação GenéticaRESUMO
Introduction: Gastrointestinal manifestations of systemic sclerosis affect up to 90% of patients, with symptoms including diarrhea and constipation. Small intestinal bacterial overgrowth is a condition associated with increased numbers of pathogenic bacteria in the small bowel. While currently unknown, it has been suggested that dysregulation of the fecal microbiota may play a role in the development of systemic sclerosis and small intestinal bacterial overgrowth. Objectives: Our study aimed to describe the fecal microbiota of patients with systemic sclerosis and compare it between those with and without a diagnosis of small intestinal bacterial overgrowth. We also compared the fecal microbiota of systemic sclerosis patients with that of healthy controls to understand the association between particular bacterial taxa and clinical gastrointestinal manifestations of systemic sclerosis. Methods: A total of 29 patients with systemic sclerosis underwent breath testing to assess for small intestinal bacterial overgrowth, provided stool samples to determine taxonomic assignments, and completed the University of California Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract 2.0, which details symptoms and quality-of-life factors. Stool samples were compared between systemic sclerosis patients with and without small intestinal bacterial overgrowth, and between patients with systemic sclerosis and a healthy control cohort (n = 20), aged 18-80 years. Results: Fecal microbiome analyses demonstrated differences between systemic sclerosis patients with and without small intestinal bacterial overgrowth and differences in the diversity of species between healthy controls and patients with systemic sclerosis. Trends were also observed in anticentromere antibody systemic sclerosis patients, including higher Alistipies indistincus spp. levels associated with increased methane levels of breath gas testing and higher Slakia spp. levels associated with increased rates of fecal soiling. Conclusions: Our results suggest that changes to the fecal microbiome occur in patients with small intestinal bacterial overgrowth and systemic sclerosis when compared to healthy controls. As a cross-sectional study, the potential pathophysiologic role of an altered microbiome in the development of systemic sclerosis was not considered and hence needs to be further investigated.
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The purpose of this study was to investigate a) the types of retention strategies used by undergraduate nursing programs for the purpose of retaining minority students, b) the rated effectiveness of the strategies, as identified by faculty in those programs, and c) whether there is a relationship between strategies rated as effective and the type of nursing program, baccalaureate (BSN) or associate (AD) degree. Administrator-selected faculty from randomly sampled BSN and AD nursing programs within a 16-state area of the southeastern United States were asked to respond to an online survey regarding the use and effectiveness of retention strategies selected from the literature. Descriptive statistics and chi-square tests for association were used to analyze the data. Of the 14 strategies included in this analysis, faculty availability and timely feedback on tests and clinical performances were used by all undergraduate programs. Organized study groups and peer mentoring were the least used strategies. Faculty from both BSN and AD programs reported using many of the strategies and rated their use as effective overall for minority nursing student retention. The highest rated strategies were those that involved direct interaction of nurse faculty and students.
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Diversidade Cultural , Educação Técnica em Enfermagem , Bacharelado em Enfermagem , Grupos Minoritários , Estudos Transversais , District of Columbia , Humanos , Mentores , Avaliação de Programas e Projetos de Saúde , Sudeste dos Estados Unidos , Ensino/métodos , Apoio ao Desenvolvimento de Recursos HumanosRESUMO
Mitogen-activated protein kinase (MAPK) cascades are rapidly activated upon plant recognition of invading pathogens. Here, we describe the use of virus-induced gene silencing (VIGS) to study the role of candidate plant MAP kinase kinase kinase (MAPKKK) homologs of human MEKK1 in pathogen-resistance pathways. We demonstrate that silencing expression of a tobacco MAPKKK, Nicotiana Protein Kinase 1 (NPK1), interferes with the function of the disease-resistance genes N, Bs2, and Rx, but does not affect Pto- and Cf4-mediated resistance. Further, NPK1-silenced plants also exhibit reduced cell size, defective cytokinesis, and an overall dwarf phenotype. Our results provide evidence that NPK1 functions in the regulation of N-, Bs2-, and Rx-mediated resistance responses and may play a role in one or more MAPK cascades, regulating multiple cellular processes.
Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Inativação Gênica/fisiologia , Sistema Imunitário/enzimologia , Imunidade Inata/imunologia , MAP Quinase Quinase Quinase 1 , MAP Quinase Quinase Quinases/imunologia , Nicotiana/enzimologia , Doenças das Plantas , Proteínas de Plantas/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Tamanho Celular/genética , Vetores Genéticos/genética , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Homologia de Sequência do Ácido Nucleico , Transdução de Sinais/genética , Nicotiana/crescimento & desenvolvimento , Nicotiana/imunologia , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/imunologiaRESUMO
A susceptibility locus for psoriasis, PSORS4, has been mapped to chromosome 1q21 in the region of the epidermal differentiation complex. The region has been refined to a 115 kb interval around the loricrin (LOR) gene. However, no evidence of association between polymorphisms in the LOR gene and psoriasis has been found. Therefore, we have analysed association to three candidate gene clusters of the region, the S100, small proline-rich protein (SPRR) and PGLYRP (peptidoglycan recognition protein) genes, which all contain functionally interesting psoriasis candidate genes. In previous studies, the SPRR and S100 genes have shown altered expression in psoriasis. Also polymorphisms in the PGLYRP genes have shown to be associated with psoriasis. We genotyped altogether 29 single nucleotide polymorphisms (SNPs) in 255 Finnish psoriasis families and analysed association with psoriasis using transmission disequilibrium test. A five-SNP haplotype of PGLYRP SNPs associated significantly with psoriasis. There was also suggestive evidence of association to SPRR gene locus in Finnish families. To confirm the putative associations, selected SNPs were genotyped also in a family collection of Swedish and Irish patients. The families supported association to the two gene regions, but there was also evidence of allelic heterogeneity.