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1.
Front Immunol ; 15: 1368516, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601146

RESUMO

Background: Differences in border zone contribute to different outcomes post-infarction, such as left ventricular aneurysm (LVA) and myocardial infarction (MI). LVA usually forms within 24 h of the onset of MI and may cause heart rupture; however, LVA surgery is best performed 3 months after MI. Few studies have investigated the LVA model, the differences in border zones between LVA and MI, and the mechanism in the border zone. Methods: The LVA, MI, and SHAM mouse models were used. Echocardiography, Masson's trichrome staining, and immunofluorescence staining were performed, and RNA sequencing of the border zone was conducted. The adipocyte-conditioned medium-treated hypoxic macrophage cell line and LVA and MI mouse models were employed to determine the effects of the hub gene, adiponectin (ADPN), on macrophages. Quantitative polymerase chain reaction (qPCR), Western blot analysis, transmission electron microscopy, and chromatin immunoprecipitation (ChIP) assays were conducted to elucidate the mechanism in the border zone. Human subepicardial adipose tissue and blood samples were collected to validate the effects of ADPN. Results: A novel, simple, consistent, and low-cost LVA mouse model was constructed. LVA caused a greater reduction in contractile functions than MI owing to reduced wall thickness and edema in the border zone. ADPN impeded cardiac edema and promoted lymphangiogenesis by increasing macrophage infiltration post-infarction. Adipocyte-derived ADPN promoted M2 polarization and sustained mitochondrial quality via the ADPN/AdipoR2/HMGB1 axis. Mechanistically, ADPN impeded macrophage HMGB1 inflammation and decreased interleukin-6 (IL6) and HMGB1 secretion. The secretion of IL6 and HMGB1 increased ADPN expression via STAT3 and the co-transcription factor, YAP, in adipocytes. Based on ChIP and Dual-Glo luciferase experiments, STAT3 promoted ADPN transcription by binding to its promoter in adipocytes. In vivo, ADPN promoted lymphangiogenesis and decreased myocardial injury after MI. These phenotypes were rescued by macrophage depletion or HMGB1 knockdown in macrophages. Supplying adipocytes overexpressing STAT3 decreased collagen disposition, increased lymphangiogenesis, and impaired myocardial injury. However, these effects were rescued after HMGB1 knockdown in macrophages. Overall, the IL6/ADPN/HMGB1 axis was validated using human subepicardial tissue and blood samples. This axis could serve as an independent factor in overweight MI patients who need coronary artery bypass grafting (CABG) treatment. Conclusion: The IL6/ADPN/HMGB1 loop between adipocytes and macrophages in the border zone contributes to different clinical outcomes post-infarction. Thus, targeting the IL6/ADPN/HMGB1 loop may be a novel therapeutic approach for cardiac lymphatic regulation and reduction of cell senescence post-infarction.


Assuntos
Proteína HMGB1 , Infarto do Miocárdio , Camundongos , Animais , Humanos , Interleucina-6/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Retroalimentação , Infarto do Miocárdio/metabolismo , Macrófagos/metabolismo , Adipócitos/metabolismo
2.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612692

RESUMO

Abscisic acid-responsive element-binding factor 1 (ABF1), a key transcription factor in the ABA signal transduction process, regulates the expression of downstream ABA-responsive genes and is involved in modulating plant responses to abiotic stress and developmental processes. However, there is currently limited research on the feedback regulation of ABF1 in ABA signaling. This study delves into the function of BcABF1 in Pakchoi. We observed a marked increase in BcABF1 expression in leaves upon ABA induction. The overexpression of BcABF1 not only spurred Arabidopsis growth but also augmented the levels of endogenous IAA. Furthermore, BcABF1 overexpression in Arabidopsis significantly decreased leaf water loss and enhanced the expression of genes associated with drought tolerance in the ABA pathway. Intriguingly, we found that BcABF1 can directly activate BcPYL4 expression, a critical receptor in the ABA pathway. Similar to BcABF1, the overexpression of BcPYL4 in Arabidopsis also reduces leaf water loss and promotes the expression of drought and other ABA-responsive genes. Finally, our findings suggested a novel feedback regulation mechanism within the ABA signaling pathway, wherein BcABF1 positively amplifies the ABA signal by directly binding to and activating the BcPYL4 promoter.


Assuntos
Ácido Abscísico , Arabidopsis , Retroalimentação , Arabidopsis/genética , Secas , Água
3.
Ren Fail ; 46(1): 2338932, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38616174

RESUMO

PURPOSE: This study aimed to elucidate the role of USP25 in a mouse model of anti-glomerular basement membrane glomerulonephritis (anti-GBM GN). METHODS: USP25-deficient anti-GBM GN mice were generated, and their nephritis progression was monitored. Naïve CD4+ T cells were isolated from spleen lymphocytes and stimulated to differentiate into Th1, Th2, and Th17 cells. This approach was used to investigate the impact of USP25 on CD4+ T lymphocyte differentiation in vitro. Furthermore, changes in USP25 expression were monitored during Th17 differentiation, both in vivo and in vitro. RESULTS: USP25-/- mice with anti-GBM GN exhibited accelerated renal function deterioration, increased infiltration of Th1 and Th17 cells, and elevated RORγt transcription. In vitro experiments demonstrated that USP25-/- CD4+ T lymphocytes had a higher proportion for Th17 cell differentiation and exhibited higher RORγt levels upon stimulation. Wild-type mice with anti-GBM GN showed higher USP25 levels compared to healthy mice, and a positive correlation was observed between USP25 levels and Th17 cell counts. Similar trends were observed in vitro. CONCLUSION: USP25 plays a crucial role in mitigating renal histopathological and functional damage during anti-GBM GN in mice. This protective effect is primarily attributed to USP25's ability to inhibit the differentiation of naïve CD4+ T cells into Th17 cells. The underlying mechanism may involve the downregulation of RORγt. Additionally, during increased inflammatory responses or Th17 cell differentiation, USP25 expression is activated, forming a negative feedback regulatory loop that attenuates immune activation.


Assuntos
Autoanticorpos , Glomerulonefrite , Nefrite , Animais , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Células Th17 , Retroalimentação , Diferenciação Celular
4.
Mikrochim Acta ; 191(5): 231, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565795

RESUMO

Blood stasis syndrome (BSS) has persistent health risks; however, its pathogenesis remains elusive. This obscurity may result in missed opportunities for early intervention, increased susceptibility to chronic diseases, and reduced accuracy and efficacy of treatments. Metabolomics, employing the matrix-assisted laser desorption/ionization (MALDI) strategy, presents distinct advantages in biomarker discovery and unraveling molecular mechanisms. Nonetheless, the challenge is to develop efficient matrices for high-sensitivity and high-throughput analysis of diverse potential biomarkers in complex biosamples. This work utilized nitrogen-doped porous transition metal carbides and nitrides (NP-MXene) as a MALDI matrix to delve into the molecular mechanisms underlying BSS pathogenesis. Structural optimization yielded heightened peak sensitivity (by 1.49-fold) and increased peak numbers (by 1.16-fold) in clinical biosamples. Validation with animal models and clinical serum biosamples revealed significant differences in metabolic fingerprints between BSS and control groups, achieving an overall diagnostic efficacy of 0.905 (95% CI, 0.76-0.979). Prostaglandin F2α was identified as a potential biomarker (diagnostics efficiency of 0.711, specificity = 0.7, sensitivity = 0.6), and pathway enrichment analysis disclosed disruptions in arachidonic acid metabolism in BSS. This innovative approach not only advances comprehension of BSS pathogenesis, but also provides valuable insights for personalized treatment and diagnostic precision.


Assuntos
Medicamentos de Ervas Chinesas , Animais , Dinoprosta , Retroalimentação , Nitrogênio , Porosidade , Compostos Orgânicos , Biomarcadores
5.
J Cell Mol Med ; 28(8): e18201, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568078

RESUMO

Sensory nerves play a crucial role in maintaining bone homeostasis by releasing Semaphorin 3A (Sema3A). However, the specific mechanism of Sema3A in regulation of bone marrow mesenchymal stem cells (BMMSCs) during bone remodelling remains unclear. The tibial denervation model was used and the denervated tibia exhibited significantly lower mass as compared to sham operated bones. In vitro, BMMSCs cocultured with dorsal root ganglion cells (DRGs) or stimulated by Sema3A could promote osteogenic differentiation through the Wnt/ß-catenin/Nrp1 positive feedback loop, and the enhancement of osteogenic activity could be inhibited by SM345431 (Sema3A-specific inhibitor). In addition, Sema3A-stimulated BMMSCs or intravenous injection of Sema3A could promote new bone formation in vivo. To sum up, the coregulation of bone remodelling is due to the ageing of BMMSCs and increased osteoclast activity. Furthermore, the sensory neurotransmitter Sema3A promotes osteogenic differentiation of BMMSCs via Wnt/ß-catenin/Nrp1 positive feedback loop, thus promoting osteogenesis in vivo and in vitro.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Osteogênese/genética , Semaforina-3A/genética , Retroalimentação , beta Catenina , Gânglios Espinais , Neuropilina-1/genética
6.
Chaos ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38572947

RESUMO

Feedback loops between strategies and the environment are commonly observed in socio-ecological, evolution-ecological, and psychology-economic systems. However, the impact of mutations in these feedback processes is often overlooked. This study proposes a novel model that integrates the public goods game with environmental feedback, considering the presence of mutations. In our model, the enhancement factor of the public goods game combines positive and negative incentives from the environment. By employing replicator-mutator (RM) equations, we provide an objective understanding of the system's evolutionary state, focusing on identifying conditions that foster cooperation and prevent the tragedy of the commons. Specifically, mutations play a crucial role in the RM dynamics, leading to the emergence of an oscillatory tragedy of the commons. By verifying the Hopf bifurcation condition, we establish the existence of a stable limit cycle, providing valuable insights into sustained oscillation strategies. Moreover, the feedback mechanism inherent in the public goods game model offers a fresh perspective on effectively addressing the classic dilemma of the tragedy of the commons.


Assuntos
Comportamento Cooperativo , Teoria do Jogo , Retroalimentação , Evolução Biológica , Mutação
7.
Med Educ Online ; 29(1): 2336332, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38560892

RESUMO

BACKGROUND: The scholarship of teaching and learning (SoTL) is a field of academic research that focuses on improving learning through reflective and informed teaching. Currently, most SoTL-related work is faculty-driven; however, student involvement in SoTL has been shown to benefit both learners and educators. Our study aims to develop a framework for increasing medical students' interest, confidence, and engagement in SoTL. METHODS: A student-led SoTL interest group was developed and a year-round program of SoTL was designed and delivered by student leaders of the group under the guidance of a faculty advisor. Individual post-session surveys were administered to evaluate participants' perceptions of each session. Pre- and post-program surveys were administered to evaluate the program impact. RESULTS: The year-round SoTL program consistently attracted the participation of medical students and faculty. Survey responses indicated strong medical student interest in the program and positive impact of the program. Increased interest and confidence in medical education research were reported by the student participants. The program design provided opportunities for student participants to network and receive ongoing feedback about medical education research they were interested or involved in. CONCLUSION: Our study provides insights for developing a framework that other institutions can reference and build upon to educate and engage students in SoTL.


Assuntos
Estudantes de Medicina , Humanos , Bolsas de Estudo , Aprendizagem , Docentes , Retroalimentação , Ensino , Currículo
8.
Nat Commun ; 15(1): 2825, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561362

RESUMO

Ten-eleven translocation (TET) 2 is an enzyme that catalyzes DNA demethylation to regulate gene expression by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine, functioning as an essential epigenetic regulator in various biological processes. However, the regulation and function of TET2 in adipocytes during obesity are poorly understood. In this study, we demonstrate that leptin, a key adipokine in mammalian energy homeostasis regulation, suppresses adipocyte TET2 levels via JAK2-STAT3 signaling. Adipocyte Tet2 deficiency protects against high-fat diet-induced weight gain by reducing leptin levels and further improving leptin sensitivity in obese male mice. By interacting with C/EBPα, adipocyte TET2 increases the hydroxymethylcytosine levels of the leptin gene promoter, thereby promoting leptin gene expression. A decrease in adipose TET2 is associated with obesity-related hyperleptinemia in humans. Inhibition of TET2 suppresses the production of leptin in mature human adipocytes. Our findings support the existence of a negative feedback loop between TET2 and leptin in adipocytes and reveal a compensatory mechanism for the body to counteract the metabolic dysfunction caused by obesity.


Assuntos
Dioxigenases , Leptina , Animais , Humanos , Masculino , Camundongos , Adipócitos/metabolismo , Peso Corporal , Dioxigenases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Retroalimentação , Leptina/metabolismo , Mamíferos/metabolismo , Obesidade/genética , Obesidade/metabolismo
9.
BMJ Open Qual ; 13(2)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580444

RESUMO

BACKGROUND: Excess opioid prescribing after surgery can lead to prolonged opioid use and diversion. We interviewed surgeons who were part of a three-group cluster-randomised controlled trial aimed at reducing prescribed opioid quantities after surgery via two versions of a monthly emailed behavioural 'nudge' (messages encouraging but not mandating compliance with social norms and clinical guidelines around prescribing) at the end of the implementation year in order to understand surgeons' reasoning for changing or continuing their prescribing behaviour as a result of the intervention and the context for their rationale. METHODS: The study took place at a large healthcare system in northern California with surgeons from three surgical specialties-orthopaedics, obstetrics/gynaecology and general surgery. Following the intervention period, we conducted semistructured interviews with 36 surgeons who had participated in the trial, ensuring representation across trial arm, specialty and changes in prescribing quantities over the year. Interviews focused on reactions to the nudges, impacts of the nudges on prescribing behaviours and other factors impacting prescribing. Three study team members coded and analysed the transcribed interviews. RESULTS: Nudges were equally effective in reducing postsurgical opioid prescribing across surgical specialties and between intervention arms. Surgeons were generally receptive to the nudge intervention, noting that it reduced the size of their discharge opioid prescriptions by improving their awareness and intentionality around prescribing. Most were unaware that clinical guidelines around opioid prescribing existed. Some had reservations regarding the accuracy and context of information provided in the nudges, the prescription quantities encouraged by the nudges and feelings of being watched or admonished. A few described discussing the nudges with colleagues. Respondents emphasised that the prescribing behaviours are informed by individual clinical experience and patient-related and procedure-related factors. CONCLUSIONS: Surgeons were open to learning about their prescribing behaviour through comparisons to guidelines or peer behaviour and incorporating this feedback as one of several factors that guide discharge opioid prescribing. Increasing awareness of clinical guidelines around opioid prescribing is important for curbing postsurgical opioid overprescribing. TRIAL REGISTRATION NUMBER: NCT05070338.


Assuntos
Analgésicos Opioides , Cirurgiões , Humanos , Analgésicos Opioides/uso terapêutico , Retroalimentação , Padrões de Prática Médica , Prescrições de Medicamentos
10.
Front Public Health ; 12: 1324940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596515

RESUMO

Background: Adverse events in the primary care setting result in a direct cost equivalent to at least 2.5% of total healthcare spending. Across OECD countries, they lead to more than seven million avoidable hospital admissions annually. In this manuscript, we describe the protocol of a trial aimed at evaluating the effectiveness of SinergiAPS (a patient-centered audit and feedback intervention) in reducing avoidable hospital admission and explore the factors that may affect its implementation. Methods: We will conduct a 24-month, parallel, open-label, multicenter, pragmatic, hybrid type 1 randomized clinical trial. 118 primary healthcare centers with wide geographical distribution in Spain will be randomly assigned (ratio 1:1) to two groups. The intervention group will receive two audits (baseline and intermediate at 12 months) based on information collected through the administration of the PREOS-PC questionnaire (a measure of patient-reported patient safety) to a convenience sample of 100 patients per center. The intervention group will receive reports on the results of both audits, along with educational resources aimed at facilitating the design and implementation of safety improvement plans. The control group will receive care as usual. The primary outcome will be the rate of avoidable hospitalizations (administrative data). Secondary outcomes: patient-reported patient safety experiences and outcomes (PREOS-PC questionnaire); patient safety culture as perceived by professionals (MOSPSC questionnaire); adverse events reported by healthcare professionals (ad hoc questionnaire); the number of safety improvement actions which the re has implemented (ad hoc questionnaire). Outcome data will be collected at baseline and 24 months follow-up. For the evaluation of the implementation of the SinergiAPS intervention, we will draw on the Consolidated Framework for Implementation Research (CFIR). We will collect and analyze qualitative and quantitative data (30 individual interviews, implementation logbooks; questionnaires for professionals from intervention centers, and level of use of the SinergiAPS web tool). Discussion: This study will expand the scarce body of evidence existing regarding the effects and implementation of interventions aimed at promoting patient and family engagement in primary healthcare, specifically for enhancing patient safety. The study has the potential to produce an impact on clinical practice, healthcare systems, and population health.Clinical Trial Registration: https://clinicaltrials.gov/study/NCT05958108?term=sinergiAPS&rank=1 (NCT05958108).


Assuntos
Segurança do Paciente , Pacientes , Humanos , Espanha , Retroalimentação , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
11.
J Cell Biol ; 223(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38573225

RESUMO

Autophagy serves as a stress response pathway by mediating the degradation of cellular material within lysosomes. In autophagy, this material is encapsulated in double-membrane vesicles termed autophagosomes, which form from precursors referred to as phagophores. Phagophores grow by lipid influx from the endoplasmic reticulum into Atg9-positive compartments and local lipid synthesis provides lipids for their expansion. How phagophore nucleation and expansion are coordinated with lipid synthesis is unclear. Here, we show that Faa1, an enzyme activating fatty acids, is recruited to Atg9 vesicles by directly binding to negatively charged membranes with a preference for phosphoinositides such as PI3P and PI4P. We define the membrane-binding surface of Faa1 and show that its direct interaction with the membrane is required for its recruitment to phagophores. Furthermore, the physiological localization of Faa1 is key for its efficient catalysis and promotes phagophore expansion. Our results suggest a positive feedback loop coupling phagophore nucleation and expansion to lipid synthesis.


Assuntos
Autofagossomos , Ácidos Graxos , Macroautofagia , Autofagia , Ácidos Graxos/metabolismo , Retroalimentação , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo
12.
PLoS One ; 19(4): e0300205, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38598479

RESUMO

BACKGROUND: Feedback in residency is a necessity for progression toward clinical competency and is included in The Accreditation Council for Graduate Medical Education (ACGME) milestones as an essential component for accreditation. PURPOSE: Our study elucidates perceptions of feedback of first-year residents and aims to identify how these perceptions change after education on building expertise through deliberate practice. METHODS: First-year internal medicine and neurology residents of a mid-sized university-affiliated residency program answered a five-question 5-point unipolar response scale questionnaire regarding feedback perceptions before and after attending a workshop about building expertise through effective feedback during residency orientation. Related-Samples Wilcoxon Signed Rank Test was applied for comparing pre- versus post-questionnaire data. RESULTS: Of 31 first-year residents, 29 completed the pre-questionnaire for a completion rate of 93.5%, while 24 of 31 completed the post-questionnaire for a completion rate of 77.4%. Of the five questions, three improved when comparing pre and post responses to, including the questions on confidence in the ability to procure feedback (p = <0.001), the effort put into procuring feedback (p = 0.001), and frequency of seeking feedback (p = 0.002). Interest in receiving feedback and the importance of feedback remained unchanged after workshop attendance. CONCLUSION: Residents should be educated on building expertise through deliberate practice and how to obtain high-quality feedback, given the emphasis and essentiality of feedback within the milestone assessment system and the core competencies of ACGME. In our study, education on these topics led to significant improvement in resident perceptions of confidence in the ability to procure feedback, effort put into procuring feedback, and frequency at which feedback would be sought.


Assuntos
Internato e Residência , Humanos , Retroalimentação , Educação de Pós-Graduação em Medicina , Competência Clínica , Acreditação , Inquéritos e Questionários
13.
BMJ Open ; 14(4): e081063, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589258

RESUMO

OBJECTIVES: Audit and Feedback (A&F) is a widely used quality improvement (QI) intervention in healthcare. However, not all feedback is accepted by professionals. While claims-based feedback has been previously used for A&F interventions, its acceptance by medical specialists is largely unknown. This study examined medical specialists' acceptance of claims-based A&F for QI. DESIGN: Qualitative design, with focus group discussions. Transcripts were analysed using discourse analysis. SETTING AND PARTICIPANTS: A total of five online focus group discussions were conducted between April 2021 and September 2022 with 21 medical specialists from varying specialties (urology; paediatric surgery; gynaecology; vascular surgery; orthopaedics and trauma surgery) working in academic or regional hospitals in the Netherlands. RESULTS: Participants described mixed views on using claims-based A&F for QI. Arguments mentioned in favour were (1) A&F stimulates reflective learning and improvement and (2) claims-based A&F is more reliable than other A&F. Arguments in opposition were that (1) A&F is insufficient to create behavioural change; (2) A&F lacks clinically meaningful interpretation; (3) claims data are invalid for feedback on QI; (4) claims-based A&F is unreliable and (5) A&F may be misused by health insurers. Furthermore, participants described several conditions for the implementation of A&F which shape their acceptance. CONCLUSIONS: Using claims-based A&F for QI is, for some clinical topics and under certain conditions, accepted by medical specialists. Acceptance of claims-based A&F can be shaped by how A&F is implemented into clinical practice. When designing A&F for QI, it should be considered whether claims data, as the most resource-efficient data source, can be used or whether it is necessary to collect more specific data.


Assuntos
Medicina , Melhoria de Qualidade , Criança , Humanos , Grupos Focais , Retroalimentação , Atenção à Saúde , Auditoria Médica
14.
Cell Mol Biol Lett ; 29(1): 56, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643083

RESUMO

During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair.


Assuntos
Chifres de Veado , MicroRNAs , Animais , Humanos , Condrogênese/genética , Retroalimentação , Cartilagem/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Diferenciação Celular/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo
15.
Proc Natl Acad Sci U S A ; 121(16): e2403316121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38593082

RESUMO

Compact chromatin is closely linked with gene silencing in part by sterically masking access to promoters, inhibiting transcription factor binding and preventing polymerase from efficiently transcribing a gene. However, a broader hypothesis suggests that chromatin compaction can be both a cause and a consequence of the locus histone modification state, with a tight bidirectional interaction underpinning bistable transcriptional states. To rigorously test this hypothesis, we developed a mathematical model for the dynamics of the HMR locus in Saccharomyces cerevisiae, that incorporates activating histone modifications, silencing proteins, and a dynamic, acetylation-dependent, three-dimensional locus size. Chromatin compaction enhances silencer protein binding, which in turn feeds back to remove activating histone modifications, leading to further compaction. The bistable output of the model was in good agreement with prior quantitative data, including switching rates from expressed to silent states (and vice versa), and protein binding/histone modification levels within the locus. We then tested the model by predicting changes in switching rates as the genetic length of the locus was increased, which were then experimentally verified. Such bidirectional feedback between chromatin compaction and the histone modification state may be a widespread and important regulatory mechanism given the hallmarks of many heterochromatic regions: physical chromatin compaction and dimerizing (or multivalent) silencing proteins.


Assuntos
Cromatina , Proteínas de Saccharomyces cerevisiae , Cromatina/genética , Cromatina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Heterocromatina/genética , Heterocromatina/metabolismo , Histonas/genética , Histonas/metabolismo , Código das Histonas , Retroalimentação , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
PLoS One ; 19(4): e0302180, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635568

RESUMO

Based on the behavioral theory of the firm, we research how performance feedback influences the formation of CEOs' passion. We articulate that previous performance directly increases CEOs' passion. Specifically, positive affective outcomes (performance above aspiration-level) advance CEOs' positive feelings and motivation toward the domains of success (obsessive passion). For instance, when a firm accomplishes performance objectives, such as reaching sales goals, CEOs' positive feelings toward developing current products would be boosted. Moreover, negative affective outcomes (performance below aspiration-level) would also positively impact CEOs' passion since the CEOs would endeavor to reduce the difference between performance and their aspiration-level. As such, performance feedback is a critical antecedent of CEOs' obsessive passion. In addition, we apply human capital as a moderator between performance feedback and CEOs' obsessive passion. Results based on multiphase survey data from 189 CEOs of Korean small- and medium-sized enterprises indicate that both positive and negative performance feedback positively increase CEOs' obsessive passion. Moreover, human capital negatively moderates the relationship between positive performance feedback and CEOs' obsessive passion and positively moderates the relationship between negative performance feedback and CEOs' obsessive passion.


Assuntos
Emoções , Motivação , Humanos , Retroalimentação , Logro , Ocupações
17.
Mol Med Rep ; 29(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38577930

RESUMO

Emerging scientific evidence has suggested that the long non­coding (lnc)RNA differentiation antagonizing non­protein coding RNA (DANCR) serves a significant role in human tumorigenesis and cancer progression; however, the precise mechanism of its function in breast cancer remains to be fully understood. Therefore, the objective of the present study was to manipulate DANCR expression in MCF7 and MDA­MB­231 cells using lentiviral vectors to knock down or overexpress DANCR. This manipulation, alongside the analysis of bioinformatics data, was performed to investigate the potential mechanism underlying the role of DANCR in cancer. The mRNA and/or protein expression levels of DANCR, miR­34c­5p and E2F transcription factor 1 (E2F1) were assessed using reverse transcription­quantitative PCR and western blotting, respectively. The interactions between these molecules were validated using chromatin immunoprecipitation and dual­luciferase reporter assays. Additionally, fluorescence in situ hybridization was used to confirm the subcellular localization of DANCR. Cell proliferation, migration and invasion were determined using 5­ethynyl­2'­deoxyuridine, wound healing and Transwell assays, respectively. The results of the present study demonstrated that DANCR had a regulatory role as a competing endogenous RNA and upregulated the expression of E2F1 by sequestering miR­34c­5p in breast cancer cells. Furthermore, E2F1 promoted DANCR transcription by binding to its promoter in breast cancer cells. Notably, the DANCR/miR­34c­5p/E2F1 feedback loop enhanced cell proliferation, migration and invasion in breast cancer cells. Thus, these findings suggested that targeting DANCR may potentially provide a promising future therapeutic strategy for breast cancer treatment.


Assuntos
Neoplasias da Mama , MicroRNAs , RNA Longo não Codificante , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Retroalimentação , Hibridização in Situ Fluorescente , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo
18.
BMC Health Serv Res ; 24(1): 479, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38632593

RESUMO

BACKGROUND: Audit and Feedback (A&F) interventions based on quality indicators have been shown to lead to significant improvements in compliance with evidence-based care including de-adoption of low-value practices (LVPs). Our primary aim was to evaluate the cost-effectiveness of adding a hypothetical A&F module targeting LVPs for trauma admissions to an existing quality assurance intervention targeting high-value care and risk-adjusted outcomes. A secondary aim was to assess how certain A&F characteristics might influence its cost-effectiveness. METHODS: We conducted a cost-effectiveness analysis using a probabilistic static decision analytic model in the Québec trauma care continuum. We considered the Québec Ministry of Health perspective. Our economic evaluation compared a hypothetical scenario in which the A&F module targeting LVPs is implemented in a Canadian provincial trauma quality assurance program to a status quo scenario in which the A&F module is not implemented. In scenarios analyses we assessed the impact of A&F characteristics on its cost-effectiveness. Results are presented in terms of incremental costs per LVP avoided. RESULTS: Results suggest that the implementation of A&F module (Cost = $1,480,850; Number of LVPs = 6,005) is associated with higher costs and higher effectiveness compared to status quo (Cost = $1,124,661; Number of LVPs = 8,228). The A&F module would cost $160 per LVP avoided compared to status quo. The A&F module becomes more cost-effective with the addition of facilitation visits; more frequent evaluation; and when only high-volume trauma centers are considered. CONCLUSION: A&F module targeting LVPs is associated with higher costs and higher effectiveness than status quo and has the potential to be cost-effective if the decision-makers' willingness-to-pay is at least $160 per LVP avoided. This likely represents an underestimate of true ICER due to underestimated costs or missed opportunity costs. Results suggest that virtual facilitation visits, frequent evaluation, and implementing the module in high-volume centers can improve cost-effectiveness.


Assuntos
Análise de Custo-Efetividade , Hospitalização , Humanos , Análise Custo-Benefício , Retroalimentação , Canadá , Anos de Vida Ajustados por Qualidade de Vida
19.
BMC Med Educ ; 24(1): 424, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641609

RESUMO

BACKGROUND: Feedback is a critical component of the learning process in a clinical setting. This study aims to explore medical residents' perspectives on feedback delivery and identify potential barriers to feedback-seeking in clinical training. METHODS: This cross-sectional study involved 180 medical residents across seventeen specialties. We employed the validated Residency Education Feedback Level Evaluation in Clinical Training (REFLECT) tool to assess residents' perspectives on their attitude toward feedback, quality of feedback, perceived importance, and reaction to feedback. Additionally, we explored barriers to feedback-seeking behavior among medical residents. RESULTS: The majority of medical residents held positive attitudes toward feedback. They agreed that feedback improves their clinical performance (77.7%), professional behavior (67.2%), and academic motivation (56.7%), while also influencing them to become a better specialist in their future career (72.8%). However, the study revealed critical deficiencies in the feedback process. Only 25.6% of residents reported receiving regular feedback and less than half reported that feedback was consistently delivered at suitable times and locations, was sufficiently clear or included actionable plans for improvement. A minority (32.2%) agreed that faculty had sufficient skills to deliver feedback effectively. Moreover, peer-to-peer feedback appeared to be a primary source of feedback among residents. Negative feedback, though necessary, often triggered feelings of stress, embarrassment, or humiliation. Notably, there were no significant differences in feedback perceptions among different specialties. The absence of a feedback-seeking culture emerged as a central barrier to feedback-seeking behavior in the clinical setting. CONCLUSIONS: Establishing shared expectations and promoting a culture of feedback-seeking could bridge the gap between residents' perceptions and faculty feedback delivery. Furthermore, recognizing the role of senior and peer residents as valuable feedback sources can contribute to more effective feedback processes in clinical training, ultimately benefiting resident development and patient care.


Assuntos
Internato e Residência , Humanos , Estudos Transversais , Retroalimentação , Motivação , Grupo Associado , Competência Clínica
20.
Exp Cell Res ; 437(2): 114012, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38565343

RESUMO

Ovarian cancer is one of the most common gynecological tumors worldwide. Despite the availability of multiple treatments for ovarian cancer, its resistance to chemotherapy remains a significant challenge. miRNAs play crucial roles in the initiation and progression of cancer by affecting processes such as differentiation, proliferation, and chemoresistance. According to microarray and qPCR analyses, miR-7704 is significantly downregulated in cisplatin-resistant cells compared to parental cells. In this study, we found that miR-7704 inhibited the proliferation and promoted cisplatin sensitivity of ovarian cancer cells in vitro and in vivo. Moreover, ectopic expression of miR-7704 had the same effect as IL2RB knockdown. Further mechanistic studies revealed that miR-7704 played an inhibitory role by regulating IL2RB expression to inactivate the AKT signaling pathway. Furthermore, IL2RB reversed the miR-7704 mediated resistance to cisplatin in ovarian cancer. Based on these findings, miR-7704 and IL2RB show the potential as novel therapeutic targets for ovarian cancer.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , MicroRNAs/metabolismo , Cisplatino/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resistencia a Medicamentos Antineoplásicos , Retroalimentação , Neoplasias Ovarianas/patologia , Carcinogênese , Transformação Celular Neoplásica , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Subunidade beta de Receptor de Interleucina-2/metabolismo , Subunidade beta de Receptor de Interleucina-2/farmacologia , Subunidade beta de Receptor de Interleucina-2/uso terapêutico
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