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1.
Teach Learn Med ; 33(3): 334-342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33706632

RESUMO

Issue: Calls to change medical education have been frequent, persistent, and generally limited to alterations in content or structural re-organization. Self-imposed barriers have prevented adoption of more radical pedagogical approaches, so recent predictions of the 'inevitability' of medical education transitioning to online delivery seemed unlikely. Then in March 2020 the COVID-19 pandemic forced medical schools to overcome established barriers overnight and make the most rapid curricular shift in medical education's history. We share the collated reports of nine medical schools and postulate how recent responses may influence future medical education. Evidence: While extraneous pandemic-related factors make it impossible to scientifically distinguish the impact of the curricular changes, some themes emerged. The rapid transition to online delivery was made possible by all schools having learning management systems and key electronic resources already blended into their curricula; we were closer to online delivery than anticipated. Student engagement with online delivery varied with different pedagogies used and the importance of social learning and interaction along with autonomy in learning were apparent. These are factors known to enhance online learning, and the student-centered modalities (e.g. problem-based learning) that included them appeared to be more engaging. Assumptions that the new online environment would be easily adopted and embraced by 'technophilic' students did not always hold true. Achieving true distance medical education will take longer than this 'overnight' response, but adhering to best practices for online education may open a new realm of possibilities. Implications: While this experience did not confirm that online medical education is really 'inevitable,' it revealed that it is possible. Thoughtfully blending more online components into a medical curriculum will allow us to take advantage of this environment's strengths such as efficiency and the ability to support asynchronous and autonomous learning that engage and foster intrinsic learning in our students. While maintaining aspects of social interaction, online learning could enhance pre-clinical medical education by allowing integration and collaboration among classes of medical students, other health professionals, and even between medical schools. What remains to be seen is whether COVID-19 provided the experience, vision and courage for medical education to change, or whether the old barriers will rise again when the pandemic is over.


Assuntos
COVID-19 , Educação a Distância , Educação de Graduação em Medicina/organização & administração , Faculdades de Medicina , Humanos , SARS-CoV-2 , Estudantes de Medicina
2.
Acad Med ; 95(9S A Snapshot of Medical Student Education in the United States and Canada: Reports From 145 Schools): S426-S430, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33626736
3.
Pharmacy (Basel) ; 8(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861770

RESUMO

Goodman and Gilman's The Pharmacological Basis of Therapeutics (GGPBT) has been a cornerstone in the education of pharmacists, physicians, and pharmacologists for decades. The objectives of this study were to describe and evaluate the 13th edition of GGPBT on bases including: (1) author characteristics; (2) recency of citations; (3) conflict of interest (CoI) disclosure; (4) expert evaluation of chapters. Contributors' (N = 115) sex, professional degrees, and presence of undisclosed potential CoI-as reported by the Center for Medicare and Medicaid's Open Payments (2013-2017)-were examined. The year of publication of citations was extracted relative to Katzung's Basic and Clinical Pharmacology (KatBCP), and DiPiro's Pharmacotherapy: A Pathophysiologic Approach (DiPPAPA). Content experts provided thorough chapter reviews. The percent of GGPBT contributors that were female (20.9%) was equivalent to those in KatBCP (17.0%). Citations in GGPBT (11.5 ± 0.2 years) were significantly older than those in KatBCP (10.4 ± 0.2) and DiPPAPA (9.1 ± 0.1, p < 0.0001). Contributors to GGPBT received USD 3 million in undisclosed remuneration (Maximum author = USD 743,718). In contrast, DiPPAPA made CoI information available. Reviewers noted several strengths but also some areas for improvement. GGPBT will continue to be an important component of the biomedical curriculum. Areas of improvement include a more diverse authorship, improved conflict of interest transparency, and a greater inclusion of more recent citations.

4.
PLoS One ; 10(9): e0136712, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26340021

RESUMO

BACKGROUND: CCN2 acts as an anabolic growth factor to regulate osteoblast differentiation and function. CCN2 is induced by TGF-ß1 and acts as a mediator of TGF-ß1 induced matrix production in osteoblasts and Src is required for CCN2 induction by TGF-ß1; however, the molecular mechanisms that control CCN2 induction in osteoblasts are poorly understood. AFAP1 binds activated forms of Src and can direct the activation of Src in certain cell types, however a role for AFAP1 downstream of TGF-ß1 or in osteoblats is undefined. In this study, we investigated the role of AFAP1 for CCN2 induction by TGF-ß1 in primary osteoblasts. RESULTS: We demonstrated that AFAP1 expression in osteoblasts occurs in a biphasic pattern with maximal expression levels occurring during osteoblast proliferation (~day 3), reduced expression during matrix production/maturation (~day 14-21), an a further increase in expression during mineralization (~day 21). AFAP1 expression is induced by TGF-ß1 treatment in osteoblasts during days 7, 14 and 21. In osteoblasts, AFAP1 binds to Src and is required for Src activation by TGF-ß1 and CCN2 promoter activity and protein induction by TGF-ß1 treatment was impaired using AFAP1 siRNA, indicating the requirement of AFAP1 for CCN2 induction by TGF-ß1. We also demonstrated that TGF-ß1 induction of extracellular matrix protein collagen XIIa occurs in an AFAP1 dependent fashion. CONCLUSIONS: This study demonstrates that AFAP1 is an essential downstream signaling component of TGF-ß1 for Src activation, CCN2 induction and collagen XIIa in osteoblasts.


Assuntos
Colágeno Tipo XII/genética , Fator de Crescimento do Tecido Conjuntivo/genética , Proteínas dos Microfilamentos/genética , Osteoblastos/efeitos dos fármacos , Proteínas Proto-Oncogênicas pp60(c-src)/genética , Fator de Crescimento Transformador beta1/farmacologia , Animais , Animais Recém-Nascidos , Sítios de Ligação , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo XII/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Regulação da Expressão Gênica , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Cultura Primária de Células , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Crânio/citologia , Crânio/efeitos dos fármacos , Crânio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
Clin Interv Aging ; 9: 1437-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25210448

RESUMO

Selective estrogen receptor modulators (SERMs) are a diverse group of nonsteroidal compounds that function as agonists or antagonists for estrogen receptors (ERs) in a target gene-specific and tissue-specific fashion. SERM specificity involves tissue-specific expression of ER subtypes, differential expression of co-regulatory proteins in various tissues, and varying ER conformational changes induced by ligand binding. To date, the major clinical applications of SERMs are their use in the prevention and treatment of breast cancer, the prevention of osteoporosis, and the maintenance of beneficial serum lipid profiles in postmenopausal women. However, SERMs have also been found to promote adverse effects, including thromboembolic events and, in some cases, carcinogenesis, that have proven to be obstacles in their clinical utility. In this review, we discuss the mechanisms of SERM tissue specificity and highlight the therapeutic application of well-known and emergent SERMs.


Assuntos
Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Feminino , Humanos , Especificidade de Órgãos , Moduladores Seletivos de Receptor Estrogênico/efeitos adversos
6.
Expert Opin Drug Discov ; 9(9): 1005-19, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24967607

RESUMO

INTRODUCTION: Palmitoylation describes the enzymatic attachment of the 16-carbon fatty acid, palmitate, to specific cysteines of proteins via a labile thioester bond. This post-translational modification increases the lipophilicity of the modified protein, thus regulating its subcellular distribution and function. The transfer of palmitate to a substrate is mediated by palmitoyl acyltransferases (PATs), while depalmitoylation is catalyzed by acyl protein thioesterases (APTs). Nearly one-third of the 23 genes that encode PATs are linked to human diseases, representing important targets for drug development. AREAS COVERED: In this review, the authors summarize the recent technical advances in the field of palmitoylation and how they will affect our ability to understand palmitoylation and its relevance to human disease. They also review the current literature describing existing palmitoylation inhibitors. The aim of this article is to increase the awareness of the importance of palmitoylation in disease by reviewing the recent progress made in identifying pharmacological modulators of PATs/APTs. It also aims to provide suggestions for general considerations in the development of selective and potent PAT inhibitors. EXPERT OPINION: Developing therapeutically useful pharmacological modulators of palmitoylation will require that they be developed within the context of well-characterized PAT/APT-related signaling systems. The successful development of potent, specific drugs in similarly complex systems suggests that development of useful drugs targeting PATs is feasible.


Assuntos
Aciltransferases/antagonistas & inibidores , Desenho de Fármacos , Lipoilação/efeitos dos fármacos , Aciltransferases/genética , Aciltransferases/metabolismo , Animais , Inibidores Enzimáticos/farmacologia , Humanos , Terapia de Alvo Molecular , Processamento de Proteína Pós-Traducional , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato
7.
J Recept Signal Transduct Res ; 34(1): 1-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24188405

RESUMO

Most of the biological effects of estrogens are mediated via the estrogen receptors (ERs) at the level of gene regulation. Recently, new information regarding the role of ERs in physiology, pathology and the mechanisms through which estrogens bring about these functions has emerged. The physiological effects of estrogen are manifested through two ER isoforms - ERα and ERß - which display distinct regions of sequence homology. The crystal structures of these receptors bound to their specific ligands (e.g. agonists or antagonists) have revealed much about how ligand binding alters receptor structure/conformation and the interaction with coactivators or corepressors as well as how it determines the cellular response to a ligand. ERs are involved in the variety of physiological and pathological activities and different cells and tissues have shown divergent responses to these two receptor isoforms. The discovery of sub-isoforms of ER alpha and beta has further complicated our understanding of how the interaction between ERs and its ligands contribute to the development of disease. Nevertheless, continuing efforts in the study of ERs have helped us to more clearly define their role in disease and to develop novel, ER-targeted therapeutics.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Transcrição Gênica , Neoplasias da Mama/patologia , Receptor beta de Estrogênio/metabolismo , Estrogênios/genética , Estrogênios/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Terapia de Alvo Molecular
8.
Curr Mol Pharmacol ; 6(3): 173-82, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24694345

RESUMO

Transcription factors (TFs) orchestrate multiple cellular processes through tight regulation via post-translational modifications (PTMs). Thus, decoding the combinations of PTMs should provide critical layer of information that can be integrated into highly specific cellular outputs to reveal a network of genes and their target-specific regulation. Protein modifications play a decisive role in various drug responses and eventually in prognosis for many life-threatening diseases, and recent studies demonstrate that TF-based drug designing must consider structural and functional changes due to PTMs, yet we are just beginning to grasp this enormity and the impact on normal development and disease pathophysiology.


Assuntos
Processamento de Proteína Pós-Traducional , Fatores de Transcrição/metabolismo , Animais , Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Humanos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Fatores de Transcrição/química
9.
Expert Opin Drug Discov ; 7(10): 863-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22992175

RESUMO

INTRODUCTION: The role of lipophilicity in drug discovery and design is a critical one. Lipophilicity is a key physicochemical property that plays a crucial role in determining ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties and the overall suitability of drug candidates. There is increasing evidence to suggest that control of physicochemical properties such as lipophilicity, within a defined optimal range, can improve compound quality and the likelihood of therapeutic success. AREAS COVERED: This review focuses on understanding lipophilicity, techniques used to measure lipophilicity, and summarizes the importance of lipophilicity in drug discovery and development, including a discussion of its impact on individual ADMET parameters as well as its overall influence on the drug discovery and design process, specifically within the past 15 years. EXPERT OPINION: A current review of the literature reveals a continued reliance on the synthesis of novel structures with increased potency, rather than a focus on maintaining optimal physicochemical properties associated with ADMET throughout drug optimization. Particular attention to the optimum region of lipophilicity, as well as monitoring of lipophilic efficiency indices, may contribute significantly to the overall quality of candidate drugs at different stages of discovery.


Assuntos
Descoberta de Drogas , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , 1-Octanol/química , Absorção , Animais , Humanos , Água/química
10.
PLoS One ; 7(4): e35258, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22539964

RESUMO

BACKGROUND: Ets-1 controls osteoblast differentiation and bone development; however, its downstream mechanism of action in osteoblasts remains largely undetermined. CCN2 acts as an anabolic growth factor to regulate osteoblast differentiation and function. CCN2 is induced by TGF-ß1 and acts as a mediator of TGF-ß1 induced matrix production in osteoblasts; however, the molecular mechanisms that control CCN2 induction are poorly understood. In this study, we investigated the role of Ets-1 for CCN2 induction by TGF-ß1 in primary osteoblasts. RESULTS: We demonstrated that Ets-1 is expressed and induced by TGF-ß1 treatment in osteoblasts, and that Ets-1 over-expression induces CCN2 protein expression and promoter activity at a level similar to TGF-ß1 treatment alone. Additionally, we found that simultaneous Ets-1 over-expression and TGF-ß1 treatment synergize to enhance CCN2 induction, and that CCN2 induction by TGF-ß1 treatment was impaired using Ets-1 siRNA, demonstrating the requirement of Ets-1 for CCN2 induction by TGF-ß1. Site-directed mutagenesis of eight putative Ets-1 motifs (EBE) in the CCN2 promoter demonstrated that specific EBE sites are required for CCN2 induction, and that mutation of EBE sites in closer proximity to TRE or SBE (two sites previously shown to regulate CCN2 induction by TGF-ß1) had a greater effect on CCN2 induction, suggesting potential synergetic interaction among these sites for CCN2 induction. In addition, mutation of EBE sites prevented protein complex binding, and this protein complex formation was also inhibited by addition of Ets-1 antibody or Smad 3 antibody, demonstrating that protein binding to EBE motifs as a result of TGF-ß1 treatment require synergy between Ets-1 and Smad 3. CONCLUSIONS: This study demonstrates that Ets-1 is an essential downstream signaling component for CCN2 induction by TGF-ß1 in osteoblasts, and that specific EBE sites in the CCN2 promoter are required for CCN2 promoter transactivation in osteoblasts.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Osteoblastos/efeitos dos fármacos , Proteína Proto-Oncogênica c-ets-1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Anticorpos/imunologia , Sítios de Ligação , Diferenciação Celular , Fator de Crescimento do Tecido Conjuntivo/genética , Humanos , Mutagênese Sítio-Dirigida , Osteoblastos/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteína Proto-Oncogênica c-ets-1/antagonistas & inibidores , Proteína Proto-Oncogênica c-ets-1/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Proteína Smad3/imunologia , Proteína Smad3/metabolismo
11.
Mol Biol Cell ; 23(10): 1976-85, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22438586

RESUMO

Antiproliferative factor (APF) is a sialoglycopeptide elevated in the urine of patients with interstitial cystitis (IC)-a chronic, painful bladder disease of unknown etiology. APF inhibits the proliferation of normal bladder epithelial and T24 bladder carcinoma cells in vitro by binding to cytoskeleton-associated protein 4 (CKAP4) and altering the transcription of genes involved in proliferation, cellular adhesion, and tumorigenesis; however, specific molecular mechanisms and effector genes that control APF's antiproliferative effects are unknown. In this study, we found that there was a 7.5-fold up-regulation of connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells treated with APF. Western blot revealed a dose-dependent increase in CCN2 protein levels, with secretion into the culture medium after APF treatment. CCN2 overexpression enhanced APF's antiproliferative activity, whereas CCN2 knockdown diminished APF-induced p53 expression. Using a luciferase reporter construct, we found that APF treatment resulted in fivefold activation of the CCN2 proximal promoter and, of importance, that small interfering RNA-mediated knockdown of CKAP4 inhibited CCN2 upregulation. In addition, we demonstrate that CKAP4 translocates to the nucleus and binds to the CCN2 proximal promoter in an APF-dependent manner, providing evidence that CCN2 regulation by APF involves CKAP4 nuclear translocation and binding to the CCN2 promoter.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Regulação da Expressão Gênica , Glicoproteínas/fisiologia , Proteínas de Membrana/metabolismo , Ativação Transcricional , Transporte Ativo do Núcleo Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana/genética , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Crit Rev Eukaryot Gene Expr ; 21(1): 43-69, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21967332

RESUMO

Connective tissue growth factor (CTGF) is a 38 kDa, cysteine rich, extracellular matrix protein composed of 4 domains or modules. CTGF has been shown to regulate a diverse array of cellular functions and has been implicated in more complex biological processes such as angiogenesis, chondrogenesis, and osteogenesis. A role for CTGF in the development and maintenance of skeletal tissues first came to light in studies demonstrating its expression in cartilage and bone cells, which was dramatically increased during skeletal repair or regeneration. The physiological significance of CTGF in skeletogenesis was confirmed in CTGF-null mice, which exhibited multiple skeletal dysmorphisms as a result of impaired growth plate chondrogenesis, angiogenesis, and bone formation/mineralization. Given the emerging importance of CTGF in osteogenesis and chondrogenesis, this review will focus on its expression in skeletal tissues, its effects on osteoblast and chondrocyte differentiation and function, and the skeletal implications of ablation or over-expression of CTGF in knockout or transgenic mouse models, respectively. In addition, this review will examine the role of integrin-mediated signaling and the regulation of CTGF expression as it relates to skeletogenesis. We will emphasize CTGF studies in bone or bone cells, and will identify opportunities for future investigations concerning CTGF and chondrogenesis/osteogenesis.


Assuntos
Desenvolvimento Ósseo/fisiologia , Fator de Crescimento do Tecido Conjuntivo/fisiologia , Peptídeos/metabolismo , Animais , Desenvolvimento Ósseo/genética , Condrogênese/genética , Condrogênese/fisiologia , Fator de Crescimento do Tecido Conjuntivo/genética , Eptifibatida , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Transgênicos , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Osteogênese/genética , Osteogênese/fisiologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
13.
PLoS One ; 6(5): e19689, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21603604

RESUMO

Intrinsically disordered (ID) regions are frequently found in the activation domains of many transcription factors including nuclear hormone receptors. It is believed that these ID regions promote molecular recognition by creating large surfaces suitable for interactions with their specific protein binding partners, which is a critical component of gene regulation by transcription factors. It has been hypothesized that conditional folding of these activation domains may be a prerequisite for their efficient interaction with specific coregulatory proteins, and subsequent transcriptional activity leading to the regulation of target gene(s). In this study, we tested whether a naturally occurring osmolyte, trehalose can promote functionally ordered conformation in glucocorticoid receptor's major activation function domain, AF1, which is found to exist as an ID protein, and requires an efficient interaction with coregulatory proteins for optimal activity. Our data show that trehalose induces an ordered conformation in AF1 such that its interaction with steroid receptor coactivator-1 (SRC-1), a critical coregulator of glucocorticoid receptor's activity, is greatly enhanced.


Assuntos
Dobramento de Proteína/efeitos dos fármacos , Receptores de Glucocorticoides/química , Trealose/farmacologia , Animais , Linhagem Celular , Haplorrinos , Coativador 1 de Receptor Nuclear/metabolismo , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/efeitos dos fármacos , Transcrição Gênica
14.
J Biol Chem ; 278(50): 50635-40, 2003 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-14522982

RESUMO

Ran GTPase has been shown to be involved in host innate immune response, and two alleles, RanT/n and RanC/d, which differ from each other by a single nucleotide, have opposite effects on host innate immune response. In this study, we showed that although intravenous administration in mice with either Ran cDNA using an identical adenovirus (Ad) vector resulted in no significant difference in vector tissue distribution, intraperitoneal administration resulted in effective vector transduction into peritoneal macrophages, coupled with a striking difference in vector tissue distribution in 2 h or less. We further demonstrated the presence of prepackaged RNA in virions of Ad vectors, in cells actively producing Ad virus particles, and in cells very shortly after Ad infection. Real-time PCR analysis confirmed the presence of prepackaged RNA and estimated the copy number to be one per viral genome. The prepackaged viral mRNA could be used for translation into proteins, as shown by experiments in which the transcriptional inhibitor actinomycin-D was used. Hence, translation of Ran proteins from prepackaged viral mRNA immediately after virus uncoating in the cytoplasm is one mechanism that would account for an early difference in Ad-vector tissue distribution after efficient gene transfer into macrophages.


Assuntos
Adenoviridae/genética , DNA Viral , RNA Mensageiro/química , RNA Viral , Proteína ran de Ligação ao GTP/genética , Infecções por Adenoviridae/genética , Alelos , Animais , Linhagem Celular , Citoplasma/metabolismo , DNA Complementar/metabolismo , Dactinomicina/farmacologia , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Inibidores da Síntese de Ácido Nucleico/farmacologia , Biossíntese de Proteínas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Distribuição Tecidual , Vírion/genética
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