RESUMEN
For high-frequency transfer of pCF10 between E. faecalis cells, induced expression of the pCF10 genes encoding conjugative machinery from the prgQ operon is required. This process is initiated by the cCF10 (C) inducer peptide produced by potential recipient cells. The expression timing of prgB, an "early" gene just downstream of the inducible promoter, has been studied extensively in single cells. However, several previous studies suggest that only 1 to 10% of donors induced for early prgQ gene expression actually transfer plasmids to recipients, even at a very high recipient population density. One possible explanation for this is that only a minority of pheromone-induced donors actually transcribe the entire prgQ operon. Such cells would not be able to functionally conjugate but might play another role in the group behavior of donors. Here, we sought to (i) simultaneously assess the presence of RNAs produced from the proximal (early induced transcripts [early Q]) and distal (late Q) portions of the prgQ operon in individual cells, (ii) investigate the prevalence of heterogeneity in induced transcript length, and (iii) evaluate the temporality of induced transcript expression. Using fluorescent in situ hybridization chain reaction (HCR) transcript labeling and single-cell microscopic analysis, we observed that most cells expressing early transcripts (QL, prgB, and prgA) also expressed late transcripts (prgJ, pcfC, and pcfG). These data support the conclusion that, after induction is initiated, transcription likely extends through the end of the conjugation machinery operon for most, if not all, induced cells.IMPORTANCE In Enterococcus faecalis, conjugative plasmids like pCF10 often carry antibiotic resistance genes. With antibiotic treatment, bacteria benefit from plasmid carriage; however, without antibiotic treatment, plasmid gene expression may have a fitness cost. Transfer of pCF10 is mediated by cell-to-cell signaling, which activates the expression of conjugation genes and leads to efficient plasmid transfer. Yet, not all donor cells in induced populations transfer the plasmid. We examined whether induced cells might not be able to functionally conjugate due to premature induced transcript termination. Single-cell analysis showed that most induced cells do, in fact, express all of the genes required for conjugation, suggesting that premature transcription termination within the prgQ operon does not account for failure of induced donor cell gene transfer.
Asunto(s)
Conjugación Genética , Enterococcus faecalis/citología , Enterococcus faecalis/genética , Operón , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enterococcus faecalis/metabolismo , Regulación Bacteriana de la Expresión Génica , Oligopéptidos/genética , Oligopéptidos/metabolismo , Feromonas/genética , Feromonas/metabolismo , Regiones Promotoras Genéticas , Análisis de la Célula IndividualRESUMEN
Enterococcal pheromone responsive conjugative plasmids like pCF10 promote horizontal spread of antibiotic resistance genes following induction of plasmid-containing cells by potential recipients. Transcription of conjugation genes from promoter PQ is inhibited by the master regulator PrgX, further repressed when PrgX is in complex with the inhibitory I peptide, and allowed when PrgX is in complex with the C inducing peptide. Single-cell analysis has shown that heterogeneity in the pheromone response is prevalent. Here, we systematically varied levels of regulatory molecules to better understand why some individual cells have increased propensity for induction. In this study, PrgX was confirmed to repress PQ in the absence of exogenous peptides in vivo, but cells with increased levels of PrgX were shown to be more prone to induction. Further, ablation of endogenous I reduced PrgX levels, resulting in reduced basal repression and loss of inducibility. Reduction of both endogenous peptides by washing increased the inducibility of cells. Together, these results show that endogenous PrgX, C, and I levels can impact the induction potential of a cell and establish the importance of basal I for regulation. These results also suggest that PrgX/C complexes may directly activate prgQ transcription, contrary to a long-standing working model.
Asunto(s)
Proteínas Bacterianas/metabolismo , Conjugación Genética , Enterococcus faecalis/metabolismo , Regulación Bacteriana de la Expresión Génica , Oligopéptidos/metabolismo , Feromonas/metabolismo , Proteínas Bacterianas/genética , Enterococcus faecalis/genética , Oligopéptidos/genética , Operón , Feromonas/genética , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína/genéticaRESUMEN
In this article, we examine how race and gender shape nurses' emotion practice. Based on audio diaries collected from 48 nurses within two Midwestern hospital systems in the United States, we illustrate the disproportionate emotional labor that emerges among women nurses of color in the white institutional space of American health care. In this environment, women of color experience an emotional double shift as a result of negotiating patient, coworker, and supervisor interactions. In confronting racist encounters, nurses of color in our sample experience additional job-related stress, must perform disproportionate amounts of emotional labor, and experience depleted emotional resources that negatively influence patient care. Methodologically, the study extends prior research by using audio diaries collected from a racially diverse sample to capture emotion as a situationally emergent and complex feature of nursing practice. We also extend research on nursing by tracing both the sources and consequences of unequal emotion practices for nurse well-being and patient care.
Asunto(s)
Emociones , Relaciones Enfermero-Paciente , Personal de Enfermería en Hospital/psicología , Grupos Raciales/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos , Racismo/psicología , Factores Sexuales , Encuestas y CuestionariosRESUMEN
Bruton's tyrosine kinase (BTK) is a member of the Tec family of cytoplasmic tyrosine kinases involved in B-cell and myeloid cell signaling. Small molecule inhibitors of BTK are being investigated for treatment of several hematologic cancers and autoimmune diseases. GDC-0853 ((S)-2-(3'-(hydroxymethyl)-1-methyl-5-((5-(2-methyl-4-(oxetan-3-yl)piperazin-1-yl)pyridin-2-yl)amino)-6-oxo-1,6-dihydro-[3,4'-bipyridin]-2'-yl)-7,7-dimethyl-3,4,7,8-tetrahydro-2H-cyclopenta[4,5]pyrrolo[1,2-a]pyrazin-1(6H)-one) is a selective and reversible oral small-molecule BTK inhibitor in development for the treatment of rheumatoid arthritis and systemic lupus erythematosus. In Sprague-Dawley (SD) rats, administration of GDC-0853 and other structurally diverse BTK inhibitors for 7 days or longer caused pancreatic lesions consisting of multifocal islet-centered hemorrhage, inflammation, fibrosis, and pigment-laden macrophages with adjacent lobular exocrine acinar cell atrophy, degeneration, and inflammation. Similar findings were not observed in mice or dogs at much higher exposures. Hemorrhage in the peri-islet vasculature emerged between four and seven daily doses of GDC-0853 and was histologically similar to spontaneously occurring changes in aging SD rats. This suggests that GDC-0853 could exacerbate a background finding in younger animals. Glucose homeostasis was dysregulated following a glucose challenge; however, this occurred only after 28 days of administration and was not directly associated with onset or severity of pancreatic lesions. There were no changes in other common serum biomarkers assessing endocrine and exocrine pancreatic function. Additionally, these lesions were not readily detectable via Doppler ultrasound, computed tomography, or magnetic resonance imaging. Our results indicate that pancreatic lesions in rats are likely a class effect of BTK inhibitors, which may exacerbate an islet-centered pathology that is unlikely to be relevant to humans.
Asunto(s)
Páncreas/efectos de los fármacos , Piperazinas/toxicidad , Inhibidores de Proteínas Quinasas/toxicidad , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Piridonas/toxicidad , Pirroles/toxicidad , Agammaglobulinemia Tirosina Quinasa , Animales , Perros , Relación Dosis-Respuesta a Droga , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Humanos , Masculino , Ratones , Páncreas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Ratas , Especificidad de la EspecieRESUMEN
PURPOSE: In the current healthcare context, large health care organizations may increasingly emphasize profit, biomedicine, efficiency, and customer service in the delivery of care. This orientation toward nursing work by large organizations may be perceived by nurses as incompatible with professional caring. METHODS: Ordinary Least Squares regression was used to explore the impact of person-organization fit (i.e., value congruence between self and employing organization) on nurses' general job satisfaction and quality of patient care (n=753). RESULTS: Nurses' perceived person-organization fit is a significant predictor of general job satisfaction and quality of patient care. CONCLUSION: The implications of our findings are discussed and recommendations for nursing leaders and future research are made.
Asunto(s)
Satisfacción en el Trabajo , Personal de Enfermería en Hospital/psicología , Calidad de la Atención de Salud , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Eukaryotic translation initiation factor 2B (eIF2B) is a key component of the integrated stress response (ISR), which regulates protein synthesis and stress granule formation in response to cellular insult. Modulation of the ISR has been proposed as a therapeutic strategy for treatment of neurodegenerative diseases such as vanishing white matter (VWM) disease and amyotrophic lateral sclerosis (ALS) based on its ability to improve cellular homeostasis and prevent neuronal degeneration. Herein, we report the small-molecule discovery campaign that identified potent, selective, and CNS-penetrant eIF2B activators using both structure- and ligand-based drug design. These discovery efforts culminated in the identification of DNL343, which demonstrated a desirable preclinical drug profile, including a long half-life and high oral bioavailability across preclinical species. DNL343 was progressed into clinical studies and is currently undergoing evaluation in late-stage clinical trials for ALS.
Asunto(s)
Esclerosis Amiotrófica Lateral , Leucoencefalopatías , Enfermedades Neurodegenerativas , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Mutación , Factor 2B Eucariótico de Iniciación/genética , Factor 2B Eucariótico de Iniciación/metabolismo , Encéfalo/metabolismo , Leucoencefalopatías/metabolismoRESUMEN
The application of modeling and simulation techniques is increasingly common in the preclinical stages of the drug development process. GDC-0917 [(S)-1-((S)-2-cyclohexyl-2-((S)-2-(methylamino)propanamido)acetyl)-N-(2-(oxazol-2-yl)-4-phenylthiazol-5-yl)pyrrolidine-2-carboxamide] is a potent second-generation antagonist of inhibitor of apoptosis (IAP) proteins that is being developed for the treatment of various cancers. GDC-0917 has low to moderate clearance in the mouse (12.0 ml/min/kg), rat (27.0 ml/min/kg), and dog (15.3 ml/min/kg), and high clearance in the monkey (67.6 ml/min/kg). Accordingly, oral bioavailability was lowest in monkeys compared with other species. Based on our experience with a prototype molecule with similar structure, in vitro-in vivo extrapolation was used to predict a moderate clearance (11.5 ml/min/kg) in humans. The predicted human volume of distribution was estimated using simple allometry at 6.69 l/kg. Translational pharmacokinetic-pharmacodynamic (PK-PD) analysis using results from MDA-MB-231-X1.1 breast cancer xenograft studies and predicted human pharmacokinetics suggests that ED50 and ED90 targets can be achieved in humans using acceptable doses (72 mg and 660 mg, respectively) and under an acceptable time frame. The relationship between GDC-0917 concentrations and pharmacodynamic response (cIAP1 degradation) was characterized using an in vitro peripheral blood mononuclear cell immunoassay. Simulations of human GDC-0917 plasma concentration-time profile and cIAP1 degradation at the 5-mg starting dose in the phase 1 clinical trial agreed well with observations. This work shows the importance of leveraging information from prototype molecules and illustrates how modeling and simulation can be used to add value to preclinical studies in the early stages of the drug development process.
Asunto(s)
Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Proteínas Inhibidoras de la Apoptosis/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/farmacocinética , Animales , Disponibilidad Biológica , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Perros , Evaluación Preclínica de Medicamentos , Femenino , Semivida , Hepatocitos/efectos de los fármacos , Humanos , Macaca fascicularis , Masculino , Ratones , Ratones SCID , Ratas , Ratas Sprague-Dawley , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
Few researchers have examined how the components of the Practice Environment Scale of the Nursing Work Index (PES-NWI) relate to nurses' well-being at multiple organizational levels. The objective of the study was to perform a multilevel assessment of the relationships of the PES-NWI subscales with three nurse outcomes: job satisfaction, emotional exhaustion, and turnover intentions. Additionally, we tested the multilevel factor structure of the PES-NWI. In a sample of 699 full-time registered nurses in 79 units and 9 branches of a hospital system, relationships of the NWI with nurse outcomes were fairly consistent across levels of analysis. However, subscales contributed differently to the three outcomes, demonstrating the complexity of environmental influences on nurses' work experience.
Asunto(s)
Ambiente de Instituciones de Salud/organización & administración , Satisfacción en el Trabajo , Personal de Enfermería en Hospital/organización & administración , Evaluación de Resultado en la Atención de Salud , Encuestas y Cuestionarios/normas , Carga de Trabajo/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Metodológica en Enfermería , Calidad de la Atención de Salud , Proyectos de Investigación , Lugar de Trabajo/organización & administración , Lugar de Trabajo/estadística & datos numéricosRESUMEN
RIPK1 is a master regulator of inflammatory signaling and cell death and increased RIPK1 activity is observed in human diseases, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). RIPK1 inhibition has been shown to protect against cell death in a range of preclinical cellular and animal models of diseases. SAR443060 (previously DNL747) is a selective, orally bioavailable, central nervous system (CNS)-penetrant, small-molecule, reversible inhibitor of RIPK1. In three early-stage clinical trials in healthy subjects and patients with AD or ALS (NCT03757325 and NCT03757351), SAR443060 distributed into the cerebrospinal fluid (CSF) after oral administration and demonstrated robust peripheral target engagement as measured by a reduction in phosphorylation of RIPK1 at serine 166 (pRIPK1) in human peripheral blood mononuclear cells compared to baseline. RIPK1 inhibition was generally safe and well-tolerated in healthy volunteers and patients with AD or ALS. Taken together, the distribution into the CSF after oral administration, the peripheral proof-of-mechanism, and the safety profile of RIPK1 inhibition to date, suggest that therapeutic modulation of RIPK1 in the CNS is possible, conferring potential therapeutic promise for AD and ALS, as well as other neurodegenerative conditions. However, SAR443060 development was discontinued due to long-term nonclinical toxicology findings, although these nonclinical toxicology signals were not observed in the short duration dosing in any of the three early-stage clinical trials. The dose-limiting toxicities observed for SAR443060 preclinically have not been reported for other RIPK1-inhibitors, suggesting that these toxicities are compound-specific (related to SAR443060) rather than RIPK1 pathway-specific.
Asunto(s)
Enfermedad de Alzheimer , Esclerosis Amiotrófica Lateral , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Enfermedad de Alzheimer/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Método Doble Ciego , Voluntarios Sanos , Humanos , Leucocitos Mononucleares , Proteína Serina-Treonina Quinasas de Interacción con Receptores/antagonistas & inhibidoresRESUMEN
Efficient horizontal gene transfer of the conjugative plasmid pCF10 from Enterococcus faecalis depends on the expression of its type 4 secretion system (T4SS) genes, controlled by the PQ promoter. Transcription from the PQ promoter is tightly regulated, partially to limit cell toxicity caused by overproduction of PrgB, a T4SS adhesin. PrgU plays an important role in regulating this toxicity by decreasing PrgB levels. PrgU has an RNA-binding fold, prompting us to test whether PrgU exerts its regulatory control through binding of prgQ transcripts. We used a combination of in vivo methods to quantify PrgU effects on prgQ transcripts at both single-cell and population levels. PrgU function requires a specific RNA sequence within an intergenic region (IGR) about 400 bp downstream of PQ. PrgU interaction with the IGR reduces levels of downstream transcripts. Single-cell expression analysis showed that cells expressing prgU decreased transcript levels more rapidly than isogenic prgU-minus cells. PrgU bound RNA in vitro without sequence specificity, suggesting that PrgU requires a specific RNA structure or one or more host factors for selective binding in vivo. PrgU binding to its IGR target might recruit RNase(s) for targeted degradation of downstream transcripts or reduce elongation of nascent transcripts beyond the IGR. IMPORTANCE Bacteria utilize type 4 secretion systems (T4SS) to efficiently transfer DNA between donor and recipient cells, thereby spreading genes encoding antibiotic resistance as well as various virulence factors. Regulation of expression of the T4SS proteins and surface adhesins in Gram-positive bacteria is crucial, as some of these are highly toxic to the cell. The significance of our research lies in identifying the novel mechanism by which PrgU performs its delicate fine-tuning of the expression levels. As prgU orthologs are present in various conjugative plasmids and transposons, our results are likely relevant to understanding of diverse clinically important transfer systems.
Asunto(s)
Proteínas Bacterianas/genética , Enterococcus faecalis/genética , Regulación Bacteriana de la Expresión Génica , Feromonas/metabolismo , Plásmidos/genética , ADN Bacteriano/genética , Operón , Feromonas/genética , Sistemas de Secreción Tipo IV/genética , Sistemas de Secreción Tipo IV/metabolismoRESUMEN
Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) regulates inflammation, cytokine release, and necroptotic cell death and is implicated in pathogenic cellular pathways in amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), and multiple sclerosis. Inhibition of RIPK1 activity protects against inflammation and cell death in multiple animal models. DNL104 is a selective, brain-penetrant inhibitor of RIPK1 phosphorylation in clinical development for AD and ALS. DNL104 was tested in 68 healthy volunteers to investigate safety and tolerability, pharmacokinetic profile in plasma and cerebrospinal fluid, and pharmacodynamic effects of RIPK1 inhibition in peripheral blood mononuclear cells in a first-in-human, placebo-controlled, double-blind, randomized single-ascending dose (SAD) and multiple-ascending dose (MAD) study. DNL104 was well-tolerated in the SAD group and during the dosing period of the MAD group. However, postdose liver toxicity in 37.5% of subjects was observed in the MAD, and assessed to be drug related. We demonstrate that DNL104 leads to RIP1 kinase inhibition, and this is not associated with central nervous system (CNS) toxicities, supporting future development of CNS penetrant RIPK1 inhibitors.
Asunto(s)
Proteína Serina-Treonina Quinasas de Interacción con Receptores/antagonistas & inhibidores , Adolescente , Adulto , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Semivida , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Fosforilación/efectos de los fármacos , Adulto JovenRESUMEN
Since its recent reformulation, alfaxalone has gained popularity as an injectable veterinary anesthetic, including promising studies demonstrating the use of alfaxalone-xylazine for anesthesia in mice. Here we sought to expand these studies by testing additional dose ranges, elaborating on physiologic monitoring, testing sex- and strain-associated differences, and evaluating efficacy during actual surgical conditions. C57BL/6J mice showed significant sex-associated differences in anesthetic sensitivity, with males requiring higher doses of alfaxalone (80-120 mg/kg IP alfaxalone with 10 mg/kg IP xylazine) than females (40-80 mg/kg IP alfaxalone with 10 mg/kg IP xylazine) to achieve a surgical plane of anesthesia. In addition, female outbred CD1 mice were less sensitive to alfaxalone than female inbred C57BL/6J mice. When used during actual surgery, alfaxalone-xylazine administered intraperitoneally provided adequate anesthesia for a model of orthopedic surgery, whereas the same anesthetic regimen during laparotomy resulted in unacceptably high mortality; survival during laparotomy increased when drugs were administered subcutaneously. These results indicate that alfaxalone-xylazine may be a viable option for injectable surgical anesthesia in mice, although strain- and sex-associated differences and alternative routes of administration should be considered when optimizing the anesthetic regimen for specific experimental conditions.
Asunto(s)
Anestésicos/farmacología , Pregnanodionas/farmacología , Xilazina/farmacología , Anestesia/veterinaria , Anestésicos/administración & dosificación , Animales , Quimioterapia Combinada/veterinaria , Femenino , Ketamina/administración & dosificación , Ciencia de los Animales de Laboratorio , Masculino , Ratones , Ratones Endogámicos C57BL , Pregnanodionas/administración & dosificación , Xilazina/administración & dosificaciónRESUMEN
Multipotent neural progenitor cells or neural stem cells (NSC) can be propagated in vitro from a variety of sources and have great potential for neural repair. Although it is well known that NSC divide in response to basic fibroblast growth factor (FGF-2) and epidermal growth factor (EGF), cofactors necessary for survival and maintenance of a multipotent potential are still a matter of debate. In the current study, we examined the requirements for NSC proliferation and survival in vitro using the neurosphere culture system. Apotransferrin (TF), along with EGF and FGF-2, was sufficient for the formation of primary neurospheres derived from embryonic rat cortices. The addition of low concentrations of insulin or insulin-like growth factor-1 (IGF-1) enhanced neurosphere size and number and was necessary for continued passaging. Both insulin and IGF-1 acted at low concentrations, suggesting that their effects were mediated by their cognate receptors, both of which were expressed by neurosphere cultures. Sphere-forming progenitors survived for long periods in culture without EGF or FGF-2 when either insulin or IGF-1 was added to the media. Cell cycle analysis determined that surviving progenitors were relatively quiescent during the period without mitogens. Upon the reintroduction of EGF and FGF-2, surviving progenitors gave rise to new spheres that produced largely glial-restricted progeny compared with sister cultures. These data indicate that the neurogenic potential of NSC may be intimately linked to a continuous exposure to mitogens.
Asunto(s)
Proliferación Celular , Insulina/fisiología , Neuronas/fisiología , Células Madre/fisiología , Transferrina/fisiología , Animales , Supervivencia Celular/fisiología , Células Cultivadas , Femenino , Neuronas/citología , Embarazo , Ratas , Ratas Sprague-Dawley , Células Madre/citologíaRESUMEN
PURPOSE: The nonclinical toxicology program described here was designed to characterize the safety profile of anti-factor D (AFD; FCFD4514S, lampalizumab) to support intravitreal (ITV) administration in patients with geographic atrophy (GA). METHODS: The toxicity of AFD was assessed in a single-dose and 6-month repeat-dose study in monkeys at doses up to 10 mg/eye. Toxicity was assessed by clinical ophthalmic examinations, intraocular pressure measurements, ocular photography, electroretinography, fluorescein angiography, optical coherence tomography, and anatomic pathology. RESULTS: Systemic exposure to AFD generally increased with the increase in dose level. The increases in mean maximal concentration and area under the curve values were roughly dose proportional. No accumulation of AFD was observed following 10 doses, and drug exposures were not affected by anti-drug antibodies. AFD was locally and systemically well tolerated in monkeys following ITV doses of up to 10 mg/eye. Ocular effects associated with AFD were limited to transient, reversible, dose-related, aqueous cell responses and injection-related, mild, vitreal cell responses. In the 6-month repeat-dose study, 2 monkeys had a nonspecific immune response to AFD that resulted in severe ocular inflammation, attributed to administration of a heterologous (humanized) protein. CONCLUSIONS: The comprehensive toxicology program in monkeys described here was designed to evaluate the safety profile of AFD and to support multiple ITV injections in the clinic. Administration of a heterologous (humanized) protein presents a challenge, and immunogenicity in nonclinical species is not predictive of immunogenicity in humans. Taken together, the results of the nonclinical program described here support the use of AFD in patients with GA.
Asunto(s)
Fragmentos Fab de Inmunoglobulinas/farmacología , Presión Intraocular/efectos de los fármacos , Soluciones Oftálmicas/farmacología , Animales , Femenino , Angiografía con Fluoresceína , Haplorrinos , Fragmentos Fab de Inmunoglobulinas/administración & dosificación , Fragmentos Fab de Inmunoglobulinas/sangre , Inyecciones Intravítreas , Masculino , Soluciones Oftálmicas/administración & dosificación , Tomografía de Coherencia ÓpticaRESUMEN
Bruton's tyrosine kinase (Btk) is a nonreceptor cytoplasmic tyrosine kinase involved in B-cell and myeloid cell activation, downstream of B-cell and Fcγ receptors, respectively. Preclinical studies have indicated that inhibition of Btk activity might offer a potential therapy in autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. Here we disclose the discovery and preclinical characterization of a potent, selective, and noncovalent Btk inhibitor currently in clinical development. GDC-0853 (29) suppresses B cell- and myeloid cell-mediated components of disease and demonstrates dose-dependent activity in an in vivo rat model of inflammatory arthritis. It demonstrates highly favorable safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles in preclinical and Phase 2 studies ongoing in patients with rheumatoid arthritis, lupus, and chronic spontaneous urticaria. On the basis of its potency, selectivity, long target residence time, and noncovalent mode of inhibition, 29 has the potential to be a best-in-class Btk inhibitor for a wide range of immunological indications.
Asunto(s)
Agammaglobulinemia Tirosina Quinasa/antagonistas & inhibidores , Antiinflamatorios/farmacología , Piperazinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Piridonas/farmacología , Agammaglobulinemia Tirosina Quinasa/efectos de los fármacos , Agammaglobulinemia Tirosina Quinasa/genética , Animales , Antiinflamatorios/farmacocinética , Antiinflamatorios/toxicidad , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Perros , Descubrimiento de Drogas , Humanos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Células de Riñón Canino Madin Darby , Modelos Moleculares , Estructura Molecular , Piperazinas/farmacocinética , Piperazinas/toxicidad , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/toxicidad , Piridonas/farmacocinética , Piridonas/toxicidad , Ratas , Ratas Endogámicas Lew , Ratas Sprague-DawleyRESUMEN
In diabetes, glucocorticoid secretion increases secondary to hyperglycemia and is associated with an extensive list of disease complications. Levels of cortisol in humans, or corticosterone in rodents, are usually measured as transitory biomarkers of stress in blood or saliva. Glucocorticoid concentrations accumulate in human or animal hair over weeks and could more accurately measure the cumulative stress burden of diseases like chronic diabetes. In this study, corticosterone levels were measured in hair in verified rodent models of diabetes mellitus. To induce type 1 diabetes, C57BL/6J mice were injected with streptozotocin and blood and hair samples were collected 28days following induction. Leptin receptor deficient (db/db) mice were used as a spontaneous model of type 2 diabetes and blood and hair samples were collected at 8weeks of age, after the development of hyperglycemia and obesity. Corticosterone levels from serum, new growth hair and total growth hair were analyzed using an enzyme immunoassay. Corticosterone levels in new growth hair and serum were significantly elevated in both models of diabetes compared to controls. In contrast, corticosterone levels in old hair growth did not differ significantly between diabetic and non-diabetic animals. Thus, hair removal and sampling of new hair growth was a more sensitive procedure for detecting changes in hair corticosterone levels induced by periods of hyperglycemia lasting for 4weeks in mice. These results validate the use of hair to measure long-term changes in corticosterone induced by diabetes in rodent models. Further studies are now needed to validate the utility of hair cortisol as a tool for measuring the stress burden of individuals with diabetes and for following the effects of long-term medical treatments.
Asunto(s)
Corticosterona/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Cabello/metabolismo , Animales , Glucemia , Peso Corporal , Cabello/crecimiento & desarrollo , Masculino , Ratones Endogámicos C57BL , Ratones Mutantes , Receptores de Leptina/deficiencia , Receptores de Leptina/genéticaRESUMEN
Buprenorphine (BPN), a mixed opioid drug with high affinity for mu (MOR) and kappa (KOR) opioid receptors, has been shown to produce behavioral responses in rodents that are similar to those of antidepressant and anxiolytic drugs. Although recent studies have identified KORs as a primary mediator of BPN's effects in rodent models of depressive-like behavior, the role of MORs in BPN's behavioral effects has not been as well explored. The current studies investigated the role of MORs in mediating conditioned approach behavior in the novelty-induced hypophagia (NIH) test, a behavioral measure previously shown to be sensitive to chronic treatment with antidepressant drugs. The effects of BPN were evaluated in the NIH test 24h post-administration in mice with genetic deletion of the MOR (Oprm1-/-) or KOR (Oprk1-/-), or after pharmacological blockade with the non-selective opioid receptor antagonist naltrexone and selective MOR antagonist cyprodime. We found that behavioral responses to BPN in the NIH test were blocked in Oprm1-/- mice, but not in Oprk1-/- mice. Both cyprodime and naltrexone significantly reduced approach latency at doses experimentally proven to antagonize the MOR. In contrast the selective MOR agonist morphine and the selective KOR antagonist nor-BNI were both ineffective. Moreover, antinociceptive studies revealed persistence of the MOR antagonist properties of BPN at 24h post-administration, the period of behavioral reactivity. These data support modulation of MOR activity as a key component of BPN's antidepressant-like effects in the NIH paradigm.
Asunto(s)
Antidepresivos/farmacología , Conducta Animal/efectos de los fármacos , Buprenorfina/farmacología , Trastornos de Alimentación y de la Ingestión de Alimentos/tratamiento farmacológico , Receptores Opioides mu/metabolismo , Animales , Conducta Alimentaria/efectos de los fármacos , Trastornos de Alimentación y de la Ingestión de Alimentos/etiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Morfinanos/farmacología , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Dimensión del Dolor/efectos de los fármacos , Tiempo de Reacción/efectos de los fármacos , Receptores Opioides kappa/deficiencia , Receptores Opioides kappa/genética , Receptores Opioides mu/genéticaRESUMEN
Pharmacogenetic studies have identified the non-synonymous single nucleotide polymorphism (A118G) in the human mu opioid receptor (MOR) gene (OPRM1) as a critical genetic variant capable of altering the efficacy of opioid therapeutics. To date few studies have explored the potential impact of the OPRM1 A118G polymorphism on the pharmacological effects of buprenorphine (BPN), a potent MOR partial agonist and kappa opioid receptor antagonist, which is approved by the FDA for the treatment of opioid addiction and chronic pain. The goal of these studies was to determine whether the MOR-mediated behavioral effects of BPN were altered in the Oprm1 A112G mouse model of the human OPRM1 A118G SNP. All studies were conducted in female, AA, AG and GG mice. BPN's maximal analgesic effect in the hot plate test was significantly blunted in AG and GG mice compared to wild type AA mice. Similarly, the BPN-induced reduction of latency to consume food in the novelty induced hypophagia test was blocked entirely in AG and GG mice compared to their AA littermates. In addition, GG mice exhibited marked reductions in psychostimulant hyperlocomotor activity compared to the AA group. In contrast, reduced immobility in the forced swim test, an effect of BPN mediated by kappa opioid receptors, was not affected by genotype. These studies demonstrate the ability of the Oprm1 A112G SNP to attenuate the analgesic, anxiolytic and hyperlocomotor effects of BPN. Overall, these data suggest that the OPRM1 A118G SNP will significantly impact the clinical efficacy of BPN in its therapeutic applications.
Asunto(s)
Analgésicos Opioides/farmacología , Buprenorfina/farmacología , Polimorfismo de Nucleótido Simple , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo , Animales , Ansiolíticos/farmacología , Conducta de Elección/efectos de los fármacos , Conducta de Elección/fisiología , Relación Dosis-Respuesta a Droga , Conducta Alimentaria/efectos de los fármacos , Conducta Alimentaria/fisiología , Femenino , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Antagonistas de Narcóticos/farmacología , Dolor/tratamiento farmacológico , Receptores Opioides mu/antagonistas & inhibidoresRESUMEN
Significant data exists to suggest that dual leucine zipper kinase (DLK, MAP3K12) is a conserved regulator of neuronal degeneration following neuronal injury and in chronic neurodegenerative disease. Consequently, there is considerable interest in the identification of DLK inhibitors with a profile compatible with development for these indications. Herein, we use structure-based drug design combined with a focus on CNS drug-like properties to generate compounds with superior kinase selectivity and metabolic stability as compared to previously disclosed DLK inhibitors. These compounds, exemplified by inhibitor 14, retain excellent CNS penetration and are well tolerated following multiple days of dosing at concentrations that exceed those required for DLK inhibition in the brain.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Precursor de Proteína beta-Amiloide/biosíntesis , Precursor de Proteína beta-Amiloide/genética , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Diseño de Fármacos , Humanos , Macaca fascicularis , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
For nurses and other caregivers there is a strong emphasis on prosocial forms of motivation, or doing the job because you want to help others, even in formal, institutionalized care settings. This emphasis is based in gendered assumptions that altruistic motivations are the "right" reasons for being a nurse and lead to the best outcomes for workers and patients. Other motivations for pursuing care work, particularly extrinsic motivation, depart from the prosocial model of care and may be indicative of substandard outcomes, but little research has examined variation in care workers' motivations for doing their jobs. In this study, we use survey data collected from 730 acute care hospital nurses working within one health care system in the Midwestern United States to examine whether different sources of motivation for being a nurse are related to nurse job burnout, negative physical symptoms, and turnover intentions. Our findings suggest that nurses who have high intrinsic and extrinsic motivation actually have better perceived health and employment outcomes (i.e., less likely to say that they will leave, lower burnout, fewer negative physical symptoms) than those with high prosocial motivation, who are more likely to report job burnout.