Receptors (United States)

Introdução: O PET-SAÚDE tem como eixo a integração ensino-serviço-comunidade, tornando-se um espaço propício para o desenvolvimento de diversas atividades nessa esfera. Na sua 10ª edição, a proposta desenvolvida por um grupo formado por tutores, preceptores, residentes e graduandos bolsistas da Universidade Regional do Cariri (URCA), Crato-CE, foi o oferecimento de um curso de qualificação em preceptoria, baseado no uso de metodologias ativas de aprendizagem. Objetivo: Este trabalho tem como objetivo relatar a experiência de participar, como graduando bolsista, na monitoria dos grupos tutoriais durante o curso de qualificação em preceptoria na Atenção Básica. Metodologia: Compreende-se, baseado na literatura, que a metodologia tradicional não é capaz de englobar o escopo teórico-prático que exige a formação em saúde, principalmente, quanto ao aprimoramento de habilidades comunicativas e colaborativas. Portanto, anterior a inauguração do curso, os bolsistas do programa passaram por uma formação em temáticas da saúde coletiva, e tiveram contato com diversas metodologias ativas, como Problem-Based Learning (PBL), GVGO, Gamificação, dentre outras. Posteriormente, nos primeiros módulos do curso, empregou-se o aprendizado de "Introdução à Preceptoria" e "Competências Colaborativas", por exemplo, através de Sala de Aula Invertida, Mapas Conceituais, GVGO e Podcasts. Resultados: As expectativas de forte engajamento deram espaço, na prática, para barreiras e fortalezas do processo. Os obstáculos estão em torno, essencialmente, do estranhamento dos profissionais com as metodologias que enfocam o aprendiz e se afastam da centralidade no professor, visto que se torna um trabalho que demanda mais tempo, esforço e resiliência para "aprender a aprender". As potencialidades estão na possibilidade de trabalhar em equipe multiprofissional, de conhecer e de se apropriar das Tecnologias Digitais da Informação e Comunicação (TDICS) e de atualizar conhecimentos sobre preceptoria na Atenção Básica, que, muitas vezes, é ofuscada pela dinâmica hospitalocêntrica do cuidado. Conclusão: A proposta de utilização de metodologias ativas em um curso de qualificação em preceptoria é inovadora e acompanha a necessidade de evolução do Sistema Único de Saúde (SUS), especialmente no âmbito de formação de recursos humanos.

The sphingosine‐1‐phosphate 1 receptor (S1P1R) is expressed by lymphocytes, dendritic cells, and vascular endothelial cells and plays a role in the regulation of chronic inflammation and lymphocyte egress from peripheral lymphoid organs. Ozanimod is an oral selective modulator of S1P1R and S1P5R receptors in clinical development for the treatment of chronic immune‐mediated, inflammatory diseases. This first‐in‐human study characterized the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ozanimod in 88 healthy volunteers using a range of single and multiple doses (7 and 28 days) and a dose‐escalation regimen. Ozanimod was generally well tolerated up to a maximum single dose of 3 mg and multiple doses of 2 mg/d, with no severe adverse events (AEs) and no dose‐limiting toxicities. The most common ozanimod‐related AEs included headache, somnolence, dizziness, nausea, and fatigue. Ozanimod exhibited linear PK, high steady‐state volume of distribution (73–101 L/kg), moderate oral clearance (204–227 L/h), and an elimination half‐life of approximately 17 to 21 hours. Ozanimod produced a robust dose‐dependent reduction in total peripheral lymphocytes, with a median decrease of 65% to 68% observed after 28 days of dosing at 1 and 1.5 mg/d, respectively. Ozanimod selectivity affected lymphocyte subtypes, causing marked decreases in cells expressing CCR7 and variable decreases in subsets lacking CCR7. A dose‐dependent negative chronotropic effect was observed following the first dose, with the dose‐escalation regimen attenuating the first‐dose negative chronotropic effect. Ozanimod safety, PK, and PD properties support the once‐daily regimens under clinical investigation.

Introduction: Ozanimod (RPC1063) is an oral, selective sphingosine 1-phosphate (S1P) 1 and 5 receptor modulator in clinical development for the treatment of relapsing multiple sclerosis and inflammatory bowel disease. Since food has the potential to significantly influence the rate and extent of drug absorption, we designed and conducted a food-effect study with ozanimod. Methods: The objective of this study was to characterize the effects of high-fat and low-fat meals on the pharmacokinetics (PK) of a single oral dose of ozanimod in healthy adult subjects. This was a randomized, open-label, 3-period, 6-sequence, crossover study. Twenty-four healthy adult subjects were enrolled to receive a single 1-mg oral dose of ozanimod under 3 different conditions separated by washout periods of 7 days: fasted (treatment A), with a standard FDA high-fat meal (treatment B), and with a low-fat meal (treatment C). PK parameters for ozanimod and its two active metabolites (RP101988 [major] and RP101075 [minor]) were calculated. Point estimates and 90% confidence intervals (CIs) about the geometric mean ratio between treatments for maximum concentration (Cmax) and overall exposure (AUC0-inf or AUC0-last) were determined using linear mixed-effects models. Results: Twenty subjects completed both treatments A and B and 23 subjects completed both treatments A and C and provided PK data for the pair-wise comparison of fed vs fasted. The 90% CIs between fed (high-fat or low-fat) and fasted treatments for the Cmax and AUC0-inf of ozanimod and RP101988 were all within the no-effect boundary of 0.80 to 1.25. For the minor metabolite RP101075, the 90% CIs between high-fat and fasted for AUC0-last and the 90% CIs between low-fat and fasted for Cmax and AUC0-last were within the no-effect boundary. While the 90% CI between high-fat and fasted treatments for RP101075 Cmax (0.76 to 0.88) fell outside the lower bound of the no-effect boundary, this decrease was not considered to be clinically meaningful. Median time to reach Cmax (Tmax) for ozanimod was delayed following a high-fat meal (12 hours) compared to fasted and lowfat meal conditions (8 hours), but the range (6 to 12 hours) was the same. Mean elimination half-life (t1/2) values for ozanimod and its active metabolites ranged from 17-21 hours and were similar across all 3 treatments. Overall, single oral doses of 1 mg ozanimod were considered generally well tolerated. Conclusion: Ozanimod may be taken with or without food.

The sphingosine 1 phosphate receptor family has been studied widely since the initial discovery of its first member, endothelium differentiation gene 1. Since this initial discovery, the family has been renamed and the primary member of the family, the S1P1 receptor, has been targeted for a variety of disease indications and successfully drugged for the treatment of patients with relapsing multiple sclerosis. Recently, the three-dimensional structure of the S1P1 receptor has been determined by X-ray crystallography and the specifics of the sphingosine 1 phosphate ligand binding pocket mapped. Key structural features for the S1P1 receptor will be reviewed and the potential binding modes of additional pharmacologically active agents against the receptor will be analyzed in an effort to better understand the structural basis of important receptor-ligand interactions.

Pharmacological activation of the S1P1 receptor (S1P1R) results in, 1) disruption of lymphocyte egress from secondary lymphoid organs, and 2) therapeutic efficacy in preclinical models of inflammatory bowel disease (IBD). However, in addition to sequestration of lymphocytes within lymph nodes, other mechanisms of action may contribute to the anti-inflammatory effect of S1P1R agonists. Aim: The aim of this study was to begin to understand the regulation of the S1P metabolic pathway in patients with ulcerative colitis (UC) and mouse models of IBD and to assess the efficacy and mechanism of action of RPC1063, a potent S1P1R agonist, in the SAMP1YitFc mouse model of IBD. Biopsies (n = 11) were collected from involved and uninvolved sites during routine endoscopy of patients with ulcerative colitis. Tissue was collected from SAMP1YitFc and non-inflamed AKR mice (n = 6–9) and RAG−/− mice adoptively transferred with CD4+CD45RBhi or CD4+CD45RBhi+lo cells (n = 3–4). S1P metabolic pathway enzymes were analyzed by RT-PCR. After the onset of ileitis RPC1063 (1.2 mg/kg/po/d), dexamethasone (4 mg/kg/po/d) or vehicle was administered for 14 days to SAMP1YitFc mice (n = 5–7). Ileitis severity was analyzed in a blinded manner by a pathologist, and tissue extracts analyzed for cytokine and chemokine protein expression. At inflamed sites, UC patient biopsies demonstrated decreased expression of S1P lyase (S1PL; 0.85 ± 0.15-fold, P = 0.001) and increased sphingosine-1 kinase (SPHK1; 5.6 ± 5.7-fold, P = 0.001). In agreement, ileum from SAMP1YitFc mice and colon from RAG−/− CD4+CD45RBhi adoptive transfer mice also show a decrease in S1PL (5.6-fold and 2.6-fold, P < 0.05) and increase in SPHK1 (1.8- and 1.9-fold, P < 0.05). Changes in expression levels correlated with disease severity in SAMP1YitFc mice. In agreement with prior studies in colitis models, a dose of RPC1063 that achieves a 68% reduction in circulating lymphocytes significantly suppressed chronic inflammation (2.1-fold, P < 0.05) and mucosal thickening (1.9-fold, P < 0.05) in the small intestine of SAMP1YitFc mice. A reduction in 18/22 elevated cytokines and chemokines was observed, with TNFα, MCP-1, MIP-1β, MIP-2, LIF, IL-6, IL-12p40, and IL-13 reaching statistical significance. These results suggest that there is dysregulation of the S1P metabolic pathway that may result in elevated S1P at sites of inflammation within the intestine of patients with UC and in animal models of IBD. RPC1063 treatment restricted lymphocyte trafficking, blunted proinflammatory cytokine and chemokine expression and ameliorated histopathological features of IBD in SAMP1YitFc mice. RPC1063 is currently in clinical development for the treatment of patients with UC and multiple sclerosis.

This chapter has reviewed the process of drug development, with emphasis on the key players and key regulations. Features of clinical trial development required for successful execution of clinical trials were reviewed along with the economic drivers for drug development. The history and impact of the key regulatory agencies and of the pediatric rule(s) on clinical trial design and execution were discussed. Finally, current trends in clinical research were examined to project the future direct of clinical research in pediatric patients. We concluded that substantial progress has been made in clinical research in pediatric patients with an increase in the number of clinical trials in children in response to the pediatric rules, resulting in better information on efficacy and optimum dosing for children. Though this activity has fostered development of a clinical trial infrastructure for clinical studies in children, much remains to be done. The future of clinical research in pediatric subjects appears both promising and challenging.

This paper describes the construction of a combinatorial artificial receptor array (CARA) and the application of the array to differentiation of proteins based on their binding patterns. Microarrays displaying 5035 unique binding environments were prepared using a library of 19 small molecule building blocks. Each building block was equipped with a carboxylic acid handle, allowing mixtures of the building blocks to be spotted onto the surface of an amine functionalized glass slide for covalent immobilization as subunits of the binding environments. This strategy employs the microarray surface as the receptor synthesis platform, which allows for flexibility in array preparation and agility in application. An advantage of the CARA strategy is the enormous flexibility it enables in the construction of alternate microarray configurations, which facilitates rapid access to the breadth and depth of binding space. Four fluorescently labeled proteins, ubiquitin, myoglobin, alpha-1-acid glycoprotein and lysozyme, were incubated with the arrays to demonstrate the reproducibility of binding and the level of differentiation that can be achieved. The binding environments are stable, scalable, and adaptable to other formats.

Nuclear receptors regulate transcription in direct response to their cognate hormonal ligands. Ligand binding leads to the dissociation of corepressors and the recruitment of coactivators. Many of these factors, acting in large complexes, have emerged as potential chromatin remodelers through intrinsic histone modifying activities. In addition, other ligand-recruited complexes appear to act more directly on the transcriptional apparatus. The DRIP complex is a 15-subunit complex required for nuclear receptor transcriptional activation in vitro. It is recruited to the receptor in response to ligand through specific interactions of one subunit, DRIP205. We present evidence that DRIP205 interacts with another member of the steroid receptor subfamily, estrogen receptor (ER). This interaction occurs in an agonist-stimulated fashion which in turn is inhibited by several ER antagonists. In vivo, a fragment of DRIP205 containing only its receptor interacting region acts to selectively inhibit ER's ability to activate transcription in response to estradiol. These observations suggest a key role for the DRIP coactivator complex in estrogen-ER signaling.