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1.
Curr Biol ; 34(8): 1705-1717.e6, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38574729

RESUMO

Plants establish symbiotic associations with arbuscular mycorrhizal fungi (AMF) to facilitate nutrient uptake, particularly in nutrient-limited conditions. This partnership is rooted in the plant's ability to recognize fungal signaling molecules, such as chitooligosaccharides (chitin) and lipo-chitooligosaccharides. In the legume Medicago truncatula, chitooligosaccharides trigger both symbiotic and immune responses via the same lysin-motif-receptor-like kinases (LysM-RLKs), notably CERK1 and LYR4. The nature of plant-fungal engagement is opposite according to the outcomes of immunity or symbiosis signaling, and as such, discrimination is necessary, which is challenged by the dual roles of CERK1/LYR4 in both processes. Here, we describe a LysM-RLK, LYK8, that is functionally redundant with CERK1 for mycorrhizal colonization but is not involved in chitooligosaccharides-induced immunity. Genetic mutation of both LYK8 and CERK1 blocks chitooligosaccharides-triggered symbiosis signaling, as well as mycorrhizal colonization, but shows no further impact on immunity signaling triggered by chitooligosaccharides, compared with the mutation of CERK1 alone. LYK8 interacts with CERK1 and forms a receptor complex that appears essential for chitooligosaccharides activation of symbiosis signaling, with the lyk8/cerk1 double mutant recapitulating the impact of mutations in the symbiosis signaling pathway. We conclude that this novel receptor complex allows chitooligosaccharides activation specifically of symbiosis signaling and helps the plant to differentiate between activation of these opposing signaling processes.


Assuntos
Quitina , Quitosana , Medicago truncatula , Micorrizas , Proteínas de Plantas , Simbiose , Micorrizas/fisiologia , Quitina/metabolismo , Medicago truncatula/microbiologia , Medicago truncatula/metabolismo , Medicago truncatula/imunologia , Medicago truncatula/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Imunidade Vegetal , Oligossacarídeos/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo
2.
Plant J ; 115(5): 1443-1457, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37248633

RESUMO

Plant immune receptors, known as NOD-like receptors (NLRs), possess unique integrated decoy domains that enable plants to attract pathogen effectors and initiate a specific immune response. The present study aimed to create a library of these integrated domains (IDs) and screen them with pathogen effectors to identify targets for effector virulence and NLR-effector interactions. This works compiles IDs found in NLRs from seven different plant species and produced a library of 78 plasmid clones containing a total of 104 IDs, representing 43 distinct InterPro domains. A yeast two-hybrid assay was conducted, followed by an in planta interaction test, using 32 conserved effectors from Ralstonia pseudosolanacearum type III. Through these screenings, three interactions involving different IDs (kinase, DUF3542, WRKY) were discovered interacting with two unrelated type III effectors (RipAE and PopP2). Of particular interest was the interaction between PopP2 and ID#85, an atypical WRKY domain integrated into a soybean NLR gene (GmNLR-ID#85). Using a Förster resonance energy transfer-fluorescence lifetime imaging microscopy technique to detect protein-protein interactions in living plant cells, PopP2 was demonstrated to physically associate with ID#85 in the nucleus. However, unlike the known WRKY-containing Arabidopsis RRS1-R NLR receptor, GmNLR-ID#85 could not be acetylated by PopP2 and failed to activate RPS4-dependent immunity when introduced into the RRS1-R immune receptor. The generated library of 78 plasmid clones, encompassing these screenable IDs, is publicly available through Addgene. This resource is expected to be valuable for the scientific community with respect to discovering targets for effectors and potentially engineering plant immune receptors.


Assuntos
Proteínas NLR , Proteínas de Plantas , Plantas , Produtos Agrícolas , Técnicas do Sistema de Duplo-Híbrido , Núcleo Celular , Fatores de Transcrição , Proteínas NLR/metabolismo , Plantas/metabolismo , Plantas/microbiologia , Proteínas de Plantas/metabolismo , Biblioteca Gênica
3.
Head Neck ; 45(6): 1530-1538, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37045788

RESUMO

BACKGROUND: We investigated the incidence and predictive factors of retropharyngeal lymph node (RPLN) metastases in patients with oropharyngeal cancer (OPC) undergoing multimodality treatment planning imaging before radiotherapy. METHODS: Consecutive patients with OPC treated with curative-intent radiotherapy from 2017 to 2019 were retrospectively analyzed. Treatment planning comprised contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography (FDG-PET) unless contraindicated. RESULTS: Of 300 patients, 66 (22%) had radiological evidence of RPLN involvement on planning images, compared to 17 (6%) on diagnostic CT alone. On multivariate analysis, RPLN involvement was statistically (p < 0.05) associated with tonsil, soft palate, and posterior pharyngeal wall primaries, and with disease extension to the soft palate or vallecula. CONCLUSIONS: Multimodality treatment planning imaging reveals a high rate of RPLN metastases from OPC compared to diagnostic CT alone. Patients with tonsil, soft palate, or posterior pharyngeal wall primaries or disease extending to the soft palate or vallecula appear at higher risk.


Assuntos
Neoplasias Orofaríngeas , Humanos , Metástase Linfática/patologia , Estudos Retrospectivos , Incidência , Neoplasias Orofaríngeas/diagnóstico por imagem , Neoplasias Orofaríngeas/terapia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética , Fluordesoxiglucose F18
4.
CJC Open ; 5(2): 148-157, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36880068

RESUMO

Background: Coronary computed tomographic angiography (CCTA) is preferable to invasive coronary angiography (ICA) for coronary artery disease (CAD) diagnosis in elective patients without known CAD. Methods: We conducted a nonrandomized interventional study involving 2 tertiary care centres in Ontario. From July 2018 to February 2020, outpatients referred for elective ICA were identified through a centralized triage process and were recommended to undergo CCTA first instead of ICA. Patients with borderline or obstructive CAD on CCTA were recommended to undergo subsequent ICA. Intervention acceptability, fidelity, and effectiveness were assessed. Results: A total of 226 patients were screened, with 186 confirmed to be eligible, of whom 166 had patient and physician approval to proceed with CCTA (89% acceptability). Among consenting patients, 156 (94%) underwent CCTA first; 43 (28%) had borderline/obstructive CAD on CCTA, and only 1 with normal/nonobstructive CAD on CCTA was referred for subsequent ICA against protocol (99% fidelity). Overall, 119 of 156 CCTA-first patients did not have ICA within the following 90 days (i.e., 76% potentially avoided ICA, due to the intervention). Among the 36 who underwent ICA post-CCTA per protocol, 24 had obstructive CAD (66.7% diagnostic yield). If all patients who were referred for and underwent ICA at either centre between July 2016 and February 2020 (n = 694 pre-implementation; n = 333 post-implementation) had had CCTA first, an additional 42 patients per 100 would have had an obstructive CAD finding on their ICA (95% confidence interval = 26-59). Conclusion: A centralized triage process, in which elective outpatients referred for ICA are instead referred for CCTA first, appears to be acceptable and effective in diagnosing obstructive CAD and improving efficiencies in our healthcare system.


Contexte: La coronarographie par tomodensitométrie (coro-TDM) est préférable à la coronarographie invasive chez les patients sans coronaropathie connue chez qui le diagnostic d'une coronaropathie n'est pas urgent. Méthodologie: Nous avons réalisé une étude interventionnelle non randomisée dans deux centres de soins tertiaires en Ontario. Les patients ambulatoires pour qui une coronarographie invasive non urgente a été demandée entre juillet 2018 et février 2020 ont été recensés par un processus centralisé de triage et se sont fait recommander de subir d'abord une coro-TDM. Les patients qui présentaient une co-ronaropathie obstructive ou dont les résultats se trouvaient tout juste à la limite de ce diagnostic lors de la coro-TDM se faisaient recommander une coronarographie invasive subséquente. L'acceptabilité de l'intervention, sa fidélité et son efficacité ont été évaluées. Résultats: Au total, 226 patients ont été sélectionnés et 186 ont été jugés admissibles. Parmi ces derniers, 166 ont accepté de subir la coro-TDM recommandée par le médecin (acceptabilité de 89 %). Parmi les patients ayant donné leur consentement, 156 (94 %) se sont d'abord soumis à une coro-TDM, et 43 (28 %) présentaient une coronaropathie obstructive ou des résultats limites selon cet examen. Seulement un patient ne présentant pas de coronaropathie ou présentant une coronaropathie non obstructive à la coro-TDM a été orienté vers une coronarographie invasive subséquente, contrairement au protocole (fidélité de 99 %). En tout, 119 des 156 patients s'étant d'abord soumis à une coro-TDM n'ont pas eu à subir une coronarographie invasive dans les 90 jours suivants (76 % d'entre eux ont potentiellement évité une coronarographie invasive grâce à cette première intervention). Parmi les 36 patients qui ont subi une coronarographie invasive après la coro-TDM, comme le recommandait le protocole, 24 présentaient une coronaropathie obstructive (rendement diagnostique de 66,7 %). Si tous les patients qui ont été orientés vers une coronarographie invasive et qui se sont soumis à cet examen dans l'un ou l'autre des centres entre juillet 2016 et février 2020 (n = 694 avant l'instauration; n = 333 après l'instauration) avaient d'abord passé une coro-TDM, une coronaropathie obstructive aurait été décelée lors de la coronarographie invasive chez 42 patients de plus par tranche de 100 patients (intervalle de confiance à 95 % : 26 à 59). Conclusion: Le recours à un processus de triage centralisé permettant de faire d'abord passer une coro-TDM aux patients ambulatoires dans une situation non urgente qui doivent subir une coronarographie invasive semble être un moyen acceptable et efficace de diagnostiquer la coronaropathie obstructive et d'améliorer l'efficacité dans notre système de santé.

5.
Front Plant Sci ; 14: 1130782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818830

RESUMO

The establishment of defense reactions to protect plants against pathogens requires the recognition of invasion patterns (IPs), mainly detected by plasma membrane-bound pattern recognition receptors (PRRs). Some IPs, also termed elicitors, are used in several biocontrol products that are gradually being developed to reduce the use of chemicals in agriculture. Chitin, the major component of fungal cell walls, as well as its deacetylated derivative, chitosan, are two elicitors known to activate plant defense responses. However, recognition of chitooligosaccharides (COS) in Vitis vinifera is still poorly understood, hampering the improvement and generalization of protection tools for this important crop. In contrast, COS perception in the model plant Arabidopsis thaliana is well described and mainly relies on a tripartite complex formed by the cell surface lysin motif receptor-like kinases (LysM-RLKs) AtLYK1/CERK1, AtLYK4 and AtLYK5, the latter having the strongest affinity for COS. In grapevine, COS perception has for the moment only been demonstrated to rely on two PRRs VvLYK1-1 and VvLYK1-2. Here, we investigated additional players by overexpressing in Arabidopsis the two putative AtLYK5 orthologs from grapevine, VvLYK5-1 and VvLYK5-2. Expression of VvLYK5-1 in the atlyk4/5 double mutant background restored COS sensitivity, such as chitin-induced MAPK activation, defense gene expression, callose deposition and conferred non-host resistance to grapevine downy mildew (Erysiphe necator). Protein-protein interaction studies conducted in planta revealed a chitin oligomer-triggered interaction between VvLYK5-1 and VvLYK1-1. Interestingly, our results also indicate that VvLYK5-1 mediates the perception of chitin but not chitosan oligomers showing a part of its specificity.

6.
J Perianesth Nurs ; 38(3): 394-397, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36503992

RESUMO

PURPOSE: Telehealth has become commonplace in many healthcare systems across the United States. Due to the COVID-19 pandemic, a large academic medical center in the southeast USA has increased the use of telehealth in the anesthesia department to complete preanesthetic assessments before the patient's surgery. This has allowed high-risk patient populations to limit potential exposure to COVID-19 and limit the financial burden of traveling from neighboring counties to complete their preanesthetic assessment in person. The purpose of this quality improvement project was to evaluate the effectiveness of a preanesthetic assessment via telehealth among patients undergoing anesthesia. DESIGN: A quality improvement project. METHODS: Two separate surveys assessing patient and provider satisfaction with telehealth preanesthesia assessments were developed. Patients undergoing anesthesia at the medical center completed a telehealth preanesthesia assessment and received a satisfaction survey via email post-procedure. Certified registered nurse anesthetists (CRNAs) who cared for patients that completed a telehealth preanesthesia assessment also received an emailed satisfaction survey. FINDINGS: Results demonstrate high satisfaction scores for both patients and providers. CONCLUSIONS: Current telehealth preanesthetic assessments prompt high satisfaction scores, supporting continued, and expanded use.


Assuntos
COVID-19 , Telemedicina , Humanos , Estados Unidos , Pandemias , Satisfação do Paciente , Satisfação Pessoal
7.
Biol Reprod ; 108(2): 279-291, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36440965

RESUMO

Mammalian folliculogenesis is a complex process that involves the regulation of chromatin structure for gene expression and oocyte meiotic resumption. The SWI/SNF complex is a chromatin remodeler using either Brahma-regulated gene 1 (BRG1) or BRM (encoded by Smarca4 and Smarca2, respectively) as its catalytic subunit. SMARCA4 loss of expression is associated with a rare type of ovarian cancer; however, its function during folliculogenesis remains poorly understood. In this study, we describe the phenotype of BRG1 mutant mice to better understand its role in female fertility. Although no tumor emerged from BRG1 mutant mice, conditional depletion of Brg1 in the granulosa cells (GCs) of Brg1fl/fl;Amhr2-Cre mice caused sterility, whereas conditional depletion of Brg1 in the oocytes of Brg1fl/fl;Gdf9-Cre mice resulted in subfertility. Recovery of cumulus-oocyte complexes after natural mating or superovulation showed no significant difference in the Brg1fl/fl;Amhr2-Cre mutant mice and significantly fewer oocytes in the Brg1fl/fl;Gdf9-Cre mutant mice compared with controls, which may account for the subfertility. Interestingly, the evaluation of oocyte developmental competence by in vitro culture of retrieved two-cell embryos indicated that oocytes originating from the Brg1fl/fl;Amhr2-Cre mice did not reach the blastocyst stage and had higher rates of mitotic defects, including micronuclei. Together, these results indicate that BRG1 plays an important role in female fertility by regulating granulosa and oocyte functions during follicle growth and is needed for the acquisition of oocyte developmental competence.


Assuntos
Cromatina , Neoplasias , Animais , Feminino , Camundongos , Montagem e Desmontagem da Cromatina , Fertilidade/genética , Mamíferos
8.
Sci Adv ; 8(35): eabq1475, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36054356

RESUMO

Ovarian fibrosis is a pathological condition associated with aging and is responsible for a variety of ovarian dysfunctions. Given the known contributions of tissue fibrosis to tumorigenesis, it is anticipated that ovarian fibrosis may contribute to ovarian cancer risk. We recently reported that diabetic postmenopausal women using metformin had ovarian collagen abundance and organization that were similar to premenopausal ovaries from nondiabetic women. In this study, we investigated the effects of aging and metformin on mouse ovarian fibrosis at a single-cell level. We discovered that metformin treatment prevented age-associated ovarian fibrosis by modulating the proportion of fibroblasts, myofibroblasts, and immune cells. Senescence-associated secretory phenotype (SASP)-producing fibroblasts increased in aged ovaries, and a unique metformin-responsive subpopulation of macrophages emerged in aged mice treated with metformin. The results demonstrate that metformin can modulate specific populations of immune cells and fibroblasts to prevent age-associated ovarian fibrosis and offers a new strategy to prevent ovarian fibrosis.


Assuntos
Metformina , Animais , Feminino , Fibroblastos , Fibrose , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Miofibroblastos , Ovário
9.
Commun Biol ; 4(1): 527, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953351

RESUMO

The ovarian surface epithelium (OSE) is a monolayer of epithelial cells surrounding the ovary that ruptures during each ovulation to allow release of the oocyte. This wound is quickly repaired, but mechanisms promoting repair are poorly understood. The contribution of tissue-resident stem cells in the homeostasis of several epithelial tissues is widely accepted, but their involvement in OSE is unclear. We show that traits associated with stem cells can be increased following exposure to the cytokine TGFB1, overexpression of the transcription factor Snai1, or deletion of Brca1. We find that stemness is often linked to mesenchymal-associated gene expression and higher activation of ERK signalling, but is not consistently dependent on their activation. Expression profiles of these populations are extremely context specific, suggesting that stemness may not be associated with a single, distinct population, but rather is a heterogeneous cell state that may emerge from diverse environmental cues. These findings support that the OSE may not require distinct stem cells for long-term maintenance, and may instead achieve this through transient dedifferentiation into a stem-like state.


Assuntos
Proteína BRCA1/metabolismo , Células Epiteliais/citologia , Ovário/citologia , Fenótipo , Fatores de Transcrição da Família Snail/metabolismo , Células-Tronco/citologia , Fator de Crescimento Transformador beta1/metabolismo , Proteína BRCA1/genética , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Ovário/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail/genética , Células-Tronco/metabolismo , Fator de Crescimento Transformador beta1/genética
10.
Can Assoc Radiol J ; 72(4): 661-668, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33461343

RESUMO

BACKGROUND: Canada began a national reform of its post-graduate medical education training programs to a Competence By Design (CBD) model. Trends from accredited neuroradiology programs from the past 10 years were investigated to inform educators and stakeholders for this process. METHODS: A 13-question electronic survey was sent to program directors of all 8 accredited neuroradiology training programs in Canada. Data was requested for each year on the 2008-2019 graduating classes. Questions pertained to program enrolment; program completion; post-training employment; and the sufficiency of 1-year training programs. RESULTS: Response rate was 100%. Over the timeframe studied, the 2-year programs increased in size (P = 0.007), while the 1-year programs remained steady (P = 0.27). 12.2% of trainees enrolled in the 2-year program dropped out after 1 year, and were considered 1-year trainees thereafter. A higher proportion of 2-year trainees obtain positions within academic institutions (89.5 vs 67.2%, P = 0.0007), whereas a higher proportion of 1-year trainees obtain positions within non-academic institutions (29.3 vs 8.1%, P = 0.0007). A higher proportion of those with Canadian board certification in diagnostic radiology who completed a 2-year program obtained a position within a Canadian academic institution compared to non-certified 2-year trainees (P < 0.001). 71.4% of program directors agreed that a 1-year program was sufficient for non-academic staff positions. CONCLUSION: The length of the training program has significant impact on employment in academic vs non-academic institutions. This information can be used to guide the upcoming CBD initiative for neuroradiology programs.


Assuntos
Currículo/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/métodos , Neuroimagem/métodos , Radiologia/educação , Canadá , Humanos , Inquéritos e Questionários/estatística & dados numéricos
11.
Mol Biol Evol ; 38(5): 1792-1808, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33306125

RESUMO

The evolutionary and adaptive potential of a pathogen is a key determinant for successful host colonization and proliferation but remains poorly known for most of the pathogens. Here, we used experimental evolution combined with phenotyping, genomics, and transcriptomics to estimate the adaptive potential of the bacterial plant pathogen Ralstonia solanacearum to overcome the quantitative resistance of the tomato cultivar Hawaii 7996. After serial passaging over 300 generations, we observed pathogen adaptation to within-plant environment of the resistant cultivar but no plant resistance breakdown. Genomic sequence analysis of the adapted clones revealed few genetic alterations, but we provide evidence that all but one were gain of function mutations. Transcriptomic analyses revealed that even if different adaptive events occurred in independently evolved clones, there is convergence toward a global rewiring of the virulence regulatory network as evidenced by largely overlapping gene expression profiles. A subset of four transcription regulators, including HrpB, the activator of the type 3 secretion system regulon and EfpR, a global regulator of virulence and metabolic functions, emerged as key nodes of this regulatory network that are frequently targeted to redirect the pathogen's physiology and improve its fitness in adverse conditions. Significant transcriptomic variations were also detected in evolved clones showing no genomic polymorphism, suggesting that epigenetic modifications regulate expression of some of the virulence network components and play a major role in adaptation as well.


Assuntos
Adaptação Biológica/genética , Ralstonia solanacearum/genética , Regulon , Evolução Biológica , Mutação com Ganho de Função , Aptidão Genética , Solanum lycopersicum/microbiologia , Ralstonia solanacearum/patogenicidade , Transcriptoma
12.
CJC Open ; 2(6): 722-725, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33305238

RESUMO

Takotsubo syndrome is a well described clinical phenomenon that often mimics acute coronary syndrome. We present an atypical case of Takotsubo syndrome, characterized by delayed troponin elevation and electrocardiogram changes suggestive of acute coronary syndrome, but a normal coronary angiogram. We describe the integration of cardiac magnetic resonance imaging to identify syndrome overlap, and discuss the utilization of diagnostic modalities beyond coronary angiogram if clinical equipoise exists, including B-type natriuretic peptide/troponin ratio, intravascular coronary imaging, and cardiac magnetic resonance imaging.


Le syndrome de Takotsubo est un phénomène clinique bien connu qui se présente souvent comme un syndrome coronarien aigu. Nous rapportons un cas atypique de syndrome de Takotsubo caractérisé par une élévation tardive du taux de troponine et par un tracé électrocardiographique évoquant un syndrome coronarien aigu, alors que la coronarographie ne révèle aucune anomalie. Nous décrivons comment utiliser l'imagerie par résonance magnétique cardiaque pour évaluer le chevauchement des deux syndromes et nous présentons l'utilisation des outils diagnostiques autres que la coronarographie en cas d'incertitude clinique absolue, notamment le rapport peptide natriurétique de type B/troponine, l'imagerie endocoronaire et l'imagerie par résonance magnétique cardiaque.

13.
Oncotarget ; 11(47): 4366-4370, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33315987

RESUMO

Ovarian aging is associated with significant changes in the structural organization of collagen, resulting in ovarian fibrosis. In many other tissues, fibrosis increases risks associated with tumorigenesis and metastasis. Thus, it is possible that ovarian fibrosis increases the risk of ovarian cancer by creating a microenvironment more permissive to tumor growth. In this research perspective, we review the impact of female reproduction on the development of ovarian fibrosis and the contributions of genetic and hormonal disruptions such as BRCA mutation, polycystic ovarian syndrome, and infertility to structural changes in the ovary and their relative risk of ovarian cancer. We also explore new fundamental questions in the field of ovarian fibrosis and possible prevention strategies such as metformin.

14.
Mol Plant Pathol ; 21(10): 1377-1388, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32770627

RESUMO

The type III secretion system with its delivered type III effectors (T3Es) is one of the main virulence determinants of Ralstonia solanacearum, a worldwide devastating plant pathogenic bacterium affecting many crop species. The pan-effectome of the R. solanacearum species complex has been exhaustively identified and is composed of more than 100 different T3Es. Among the reported strains, their content ranges from 45 to 76 T3Es. This considerably large and varied effectome could be considered one of the factors contributing to the wide host range of R. solanacearum. In order to understand how R. solanacearum uses its T3Es to subvert the host cellular processes, many functional studies have been conducted over the last three decades. It has been shown that R. solanacearum effectors, as those from other plant pathogens, can suppress plant defence mechanisms, modulate the host metabolism, or avoid bacterial recognition through a wide variety of molecular mechanisms. R. solanacearum T3Es can also be perceived by the plant and trigger immune responses. To date, the molecular mechanisms employed by R. solanacearum T3Es to modulate these host processes have been described for a growing number of T3Es, although they remain unknown for the majority of them. In this microreview, we summarize and discuss the current knowledge on the characterized R. solanacearum species complex T3Es.


Assuntos
Plantas/microbiologia , Ralstonia solanacearum/patogenicidade , Sistemas de Secreção Tipo III , Proteínas de Bactérias/metabolismo , Perfilação da Expressão Gênica , Interações Hospedeiro-Parasita , Doenças das Plantas/microbiologia , Imunidade Vegetal , Plantas/imunologia , Sistemas de Secreção Tipo III/imunologia , Sistemas de Secreção Tipo III/metabolismo , Virulência , Fatores de Virulência/metabolismo
15.
Int J Mol Sci ; 21(14)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679765

RESUMO

The implications of the epithelial-mesenchymal transition (EMT) mechanisms in the initiation and progression of epithelial ovarian cancer (EOC) remain poorly understood. We have previously shown that suppression of the antigen receptor LY75 directs mesenchymal-epithelial transition (MET) in EOC cell lines with the mesenchymal phenotype, associated with the loss of Wnt/ß-catenin signaling activity. In the present study, we used the LY75-mediated modulation of EMT in EOC cells as a model in order to investigate in vivo the specific role of EOC cells, with an epithelial (E), mesenchymal (M) or mixed epithelial plus mesenchymal (E+M) phenotype, in EOC initiation, dissemination and treatment response, following intra-bursal (IB) injections of SKOV3-M (control), SKOV3-E (Ly75KD) and a mixed population of SKOV3-E+M cells, into severe combined immunodeficiency (SCID) mice. We found that the IB-injected SKOV3-E cells displayed considerably higher metastatic potential and resistance to treatment as compared to the SKOV3-M cells, due to the acquisition of a Ly75KD-mediated hybrid phenotype and stemness characteristics. We also confirmed in vivo that the LY75 depletion directs suppression of the Wnt/ß-catenin pathway in EOC cells, suggestive of a protective role of this pathway in EOC etiology. Moreover, our data raise concerns regarding the use of LY75-targeted vaccines for dendritic-cell EOC immunotherapy, due to the possible occurrence of undesirable side effects.


Assuntos
Antígenos CD/genética , Carcinogênese/genética , Carcinoma Epitelial do Ovário/genética , Regulação Neoplásica da Expressão Gênica , Lectinas Tipo C/genética , Antígenos de Histocompatibilidade Menor/genética , Neoplasias Ovarianas/genética , Receptores de Superfície Celular/genética , Animais , Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos SCID , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Invasividade Neoplásica/prevenção & controle , Neoplasias Experimentais , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia
17.
Reprod Fertil Dev ; 30(7): 980-990, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30447702

RESUMO

Genomic selection is accelerating genetic gain in dairy cattle. Decreasing generation time by using younger gamete donors would further accelerate breed improvement programs. Although ovarian stimulation of peripubertal animals is possible and embryos produced in vitro from the resulting oocytes are viable, developmental competence is lower than when sexually mature cows are used. The aim of the present study was to shed light on how oocyte developmental competence is acquired as a heifer ages. Ten peripubertal Bos taurus Holstein heifers underwent ovarian stimulation cycles at the ages of 8, 11 (mean 10.8) and 14 (mean 13.7) months. Collected oocytes were fertilised in vitro with spermatozoa from the same adult male. Each heifer served as its own control. The transcriptomes of granulosa cells recovered with the oocytes were analysed using microarrays. Differential expression of certain genes was measured using polymerase chain reaction. Principal component analysis of microarray data revealed that the younger the animal, the more distinctive the gene expression pattern. Using ingenuity pathway analysis (IPA) and NetworkAnalyst (www.networkanalyst.ca), the main biological functions affected in younger donors were identified. The results suggest that cell differentiation, inflammation and apoptosis signalling are less apparent in peripubertal donors. Such physiological traits have been associated with a lower basal concentration of LH.


Assuntos
Transferência Embrionária/veterinária , Células da Granulosa/metabolismo , Indução da Ovulação , Transcriptoma , Fatores Etários , Animais , Bovinos , Técnicas de Cultura Embrionária/veterinária , Feminino , Recuperação de Oócitos/veterinária , Oócitos/metabolismo
18.
Reproduction ; 156(3): 239-248, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29907662

RESUMO

The use of younger gamete donors in dairy cattle genetic selection programs significantly accelerates genetic gains by decreasing the interval between generations. Ovarian stimulation (OS) and the practice of follicle-stimulating hormone (FSH) withdrawal, also known as coasting, are intensively used in pre-pubertal heifers without detrimental effects on subsequent reproductive performance but generally with lower embryo yields. However, recent data from embryo transfer programs showed similar embryo yields in younger and sexually mature animals but with a significant difference in the coasting period. The aim of the present study was to identify a set of granulosa cell biomarkers capable of distinguishing optimal follicle differentiation from late differentiation and atresia in order to assess the differences in coasting dynamics between pre- and post-pubertal donors. We integrated transcriptomic data sets from a public depository and used vote counting meta-analysis in order to elucidate the molecular changes occurring in granulosa cells during late follicle differentiation and atresia. The meta-analysis revealed the gene expression associated with follicle demise, and most importantly, identified potential biomarkers of that status in bovine granulosa cells. The comparison of the expression of six biomarkers between pre- and post-pubertal donors revealed that younger donors had more signs of atresia after the same period of coasting. We found different follicular dynamics following coasting in younger donors. It is possible that younger donors are less capable to sustain follicular survival most likely due to insufficient luteinizing hormone signaling. In summary, the pre-pubertal status influences follicular dynamics and reduces the oocyte developmental competence curve following OS and FSH withdrawal in heifers.


Assuntos
Biomarcadores/análise , Bovinos/fisiologia , Atresia Folicular/fisiologia , Células da Granulosa/química , Indução da Ovulação/veterinária , Envelhecimento , Animais , Feminino , Atresia Folicular/genética , Expressão Gênica , Hormônio Luteinizante/metabolismo , Doação de Oócitos/veterinária , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Indução da Ovulação/métodos , Reprodutibilidade dos Testes , Maturidade Sexual , Transdução de Sinais , Transcriptoma
19.
Clin Interv Aging ; 13: 843-852, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29765209

RESUMO

PURPOSE: Recent evidence supports the prognostic significance of frailty for functional decline and poor health outcomes in patients with chronic kidney disease. Yet, despite the development of clinical tools to screen for frailty, little is known about the experiential impact of screening for frailty in this setting. The Frailty Assessment for Care Planning Tool (FACT) evaluates frailty across 4 domains: mobility, function, social circumstances, and cognition. The purpose of this qualitative study was as follows: 1) explore the nurse experience of screening for frailty using the FACT tool in a specialized outpatient renal clinic; 2) determine how, if at all, provider perceptions of frailty changed after implementation of the frailty screening tool; and 3) determine the perceived factors that influence uptake and administration of the FACT screening tool in a specialized clinical setting. METHODS: A semi-structured interview of 5 nurses from the Nova Scotia Health Authority, Central Zone Renal Clinic was conducted. A grounded theory approach was used to generate thematic categories and analysis models. RESULTS: Four primary themes emerged in the data analysis: "we were skeptical", "we made it work", "we learned how", and "we understand". As the renal nurses gained a sense of confidence in their ability to implement the FACT tool, initial barriers to implementation were attenuated. Implementation factors - such as realistic goals, clear guidelines, and ongoing training - were important factors for successful uptake of the frailty screening initiative. CONCLUSION: Nurse participants reported an overall positive experience using the FACT method to screen for frailty and indicated that their understanding of the multiple dimensions and subtleties of "frailty" were enhanced. Future nurse-led FACT screening initiatives should incorporate those factors identified as being integral to program success: realistic goals, clear guidelines, and ongoing training. Adopting the evaluation of frailty as a priority within clinical departments will encourage sustainability.


Assuntos
Fragilidade/diagnóstico , Avaliação Geriátrica/métodos , Avaliação em Enfermagem/métodos , Planejamento de Assistência ao Paciente/normas , Insuficiência Renal Crônica , Idoso , Atitude do Pessoal de Saúde , Canadá , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pesquisa Qualitativa , Melhoria de Qualidade , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/enfermagem , Insuficiência Renal Crônica/terapia
20.
Biol Reprod ; 99(4): 877-887, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29668885

RESUMO

In recent years, exciting progress was made to improve the embryo outcome after ovarian stimulation in domestic animals. The practice of follicle-stimulating hormone (FSH) withdrawal, which is defined as the period of time between the last injection of FSH and oocyte retrieval, resulted in embryo yields significantly superior. Since then, specific changes in the transcriptome of granulosa cells were associated with the increase and also the decline in oocyte developmental competence following the FSH decline. In this study, we integrated large datasets from a public depository using a meta-analysis in order to elucidate the molecular changes occurring in granulosa cells following FSH decline in association with oocyte developmental competence. The meta-analysis revealed that the gene expression patterns observed during this period resulted from the downregulation of proliferative signals, and the upregulation of differentiation signals and early apoptotic signals. Additionally, FSH decline induced cellular hypoxia and triggered the expression of proinflammatory molecules which resulted in early atresia and mimicked the luteinizing hormone (LH) surge signaling to ovulation. To characterize this unique differentiation period, we suggest using the term "follicle capacitation" to refer to the functional changes occurring within the follicle in order to prepare the molecular machinery for the LH surge and ovulation following FSH decline. During this period, the follicle confers the oocyte with developmental competence to become a viable embryo. However, if this period is not rapidly followed by an LH surge, apoptosis signals are increased to generate follicular atresia and decrease oocyte quality.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/metabolismo , Folículo Ovariano/metabolismo , Animais , Bovinos , Feminino , Redes Reguladoras de Genes , Oócitos/metabolismo , Oogênese , Indução da Ovulação/veterinária , Transcriptoma
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