RESUMO
Alterations in dendrite branching and morphology are present in many neurodegenerative diseases. These variations disrupt postsynaptic transmission and affect neuronal communication. Thus, it is important to understand the molecular mechanisms that regulate dendritogenesis and how they go awry during disease states. Previously, our laboratory showed that cypin, a mammalian guanine deaminase, increases dendrite number when overexpressed and decreases dendrite number when knocked down in cultured hippocampal neurons. Here, we report that exposure to brain-derived neurotrophic factor (BDNF), an important mediator of dendrite arborization, for 72 h but not for 24 h or less increases cypin mRNA and protein levels in rat hippocampal neurons. BDNF signals through cypin to regulate dendrite number, since knocking down cypin blocks the effects of BDNF. Furthermore, BDNF increases cypin levels via mitogen-activated protein kinase and transcription-dependent signaling pathways. Moreover, the cypin promoter region contains putative conserved cAMP response element (CRE) regions, which we found can be recognized and activated by CRE-binding protein (CREB). In addition, exposure of the neurons to BDNF increased CREB binding to the cypin promoter and, in line with these data, expression of a dominant negative form of CREB blocked BDNF-promoted increases in cypin protein levels and proximal dendrite branches. Together, these studies suggest that BDNF increases neuronal cypin expression by the activation of CREB, increasing cypin transcription leading to increased protein expression, thus identifying a novel pathway by which BDNF shapes the dendrite network.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Proteínas de Transporte/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Dendritos/efeitos dos fármacos , Guanina Desaminase/genética , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Células Cultivadas , Imunoprecipitação da Cromatina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dendritos/genética , Dendritos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Guanina Desaminase/metabolismo , Hipocampo/metabolismo , Imuno-Histoquímica , Neurônios/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transcrição GênicaRESUMO
Background. Inappropriate antibiotic prescribing can lead to antimicrobial resistance and drug side effects. Tools that assist general practitioners (GPs) in prescribing decisions may help to optimize prescribing. The aim of this study was to explore the use, acceptability, and feasibility of a clinical decision support (CDS) tool that incorporates evidence-based guidelines and consumer information that integrates with the electronic medical record (EMR). Methods. Eight GPs completed an interview and brief survey after participating in 2 simulated consultations. The survey consisted of demographic questions, perception of realism and representativeness of consultations, Post-Study System Usability Questionnaire, and System Usability Scale. Qualitative data were analyzed using framework analysis. Video data were reviewed, with length of consultation and time spent using the CDS tool documented. Results. Survey responses indicated that all GPs thought the consultations were "real" and representative of real-life consultations; 7 of 8 GPs were satisfied with usability of the tool. Key qualitative findings included that the tool assisted with clinical decision making and informed appropriate antibiotic prescribing. Accessibility and ease of use, including content (guideline and patient education resources), layout, and format, were key factors that determined whether GPs said that they would access the tool in everyday practice. Integration of the tool at multiple sites within the EMR facilitated access to guidelines and assisted in ensuring that the tool fit the clinical workflow. Conclusion. Our CDS tool was acceptable to GPs. Key features required for the tool were easy navigation, clear and useful guideline content, ability to fit into the clinical workflow, and incorporation into the EMR. Piloting of the tool in general practices to assess the impact and feasibility of use in real-world consultations will now be undertaken.
Assuntos
Gestão de Antimicrobianos/métodos , Sistemas de Apoio a Decisões Clínicas/normas , Padrões de Prática Médica/normas , Adulto , Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/normas , Atitude do Pessoal de Saúde , Austrália , Feminino , Medicina Geral/instrumentação , Medicina Geral/métodos , Medicina Geral/normas , Humanos , Entrevistas como Assunto/métodos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Managing type 2 diabetes (T2D) requires progressive lifestyle changes and, sometimes, pharmacological treatment intensification. General practitioners (GPs) are integral to this process but can find pharmacological treatment intensification challenging because of the complexity of continually emerging treatment options. OBJECTIVE: This study aimed to use a co-design method to develop and pretest a clinical decision support (CDS) tool prototype (GlycASSIST) embedded within an electronic medical record, which uses evidence-based guidelines to provide GPs and people with T2D with recommendations for setting glycated hemoglobin (HbA1c) targets and intensifying treatment together in real time in consultations. METHODS: The literature on T2D-related CDS tools informed the initial GlycASSIST design. A two-part co-design method was then used. Initial feedback was sought via interviews and focus groups with clinicians (4 GPs, 5 endocrinologists, and 3 diabetes educators) and 6 people with T2D. Following refinements, 8 GPs participated in mock consultations in which they had access to GlycASSIST. Six people with T2D viewed a similar mock consultation. Participants provided feedback on the functionality of GlycASSIST and its role in supporting shared decision making (SDM) and treatment intensification. RESULTS: Clinicians and people with T2D believed that GlycASSIST could support SDM (although this was not always observed in the mock consultations) and individualized treatment intensification. They recommended that GlycASSIST includes less information while maintaining relevance and credibility and using graphs and colors to enhance visual appeal. Maintaining clinical autonomy was important to GPs, as they wanted the capacity to override GlycASSIST's recommendations when appropriate. Clinicians requested easier screen navigation and greater prescribing guidance and capabilities. CONCLUSIONS: GlycASSIST was perceived to achieve its purpose of facilitating treatment intensification and was acceptable to people with T2D and GPs. The GlycASSIST prototype is being refined based on these findings to prepare for quantitative evaluation.
RESUMO
Media supplementation with collagen hydrolysate was hypothesized to increase the collagen content in engineered cartilage. By d28, hydrolysate at 0.5 mg/mL increased type II collagen content and 1 mg/mL increased mechanical properties, total collagen content, and type II collagen content over controls. By d42, however, controls possessed the highest GAG content and compressive Young's modulus. Real-time PCR found that 1 mg/mL increased type II collagen gene expression in d0 constructs, but increased MMP expression with no effect on type II collagen on d28. A 10 mg/mL concentration produced the lowest tissue properties, the lowest type II collagen gene expression on d0, and the highest MMP gene expression on d28. These results indicate that the duration of culture modulates the response of chondrocytes to collagen hydrolysate in 3D culture, transforming the response from positive to negative. Therefore, collagen hydrolysate as a media supplement is not a viable long-term method to improve the collagen content of engineered cartilage tissue.