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1.
J Antimicrob Chemother ; 74(7): 1894-1903, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30891606

RESUMEN

OBJECTIVES: To identify the transporters involved in renal elimination of relebactam, and to assess the potential of relebactam as a perpetrator or victim of drug-drug interactions (DDIs) for major drug transporters. METHODS: A series of bidirectional transport, uptake and inhibition studies were conducted in vitro using transfected cell lines and membrane vesicles. The inhibitory effects of relebactam on major drug transporters, as well as the inhibitory effects of commonly used antibiotics/antifungals on organic anion transporter (OAT) 3-mediated uptake of relebactam, were assessed. RESULTS: Relebactam was shown to be a substrate of OAT3, OAT4, and multidrug and toxin extrusion (MATE) proteins MATE1 and MATE2K. Relebactam did not show profound inhibition across a panel of transporters, including organic anion-transporting polypeptides 1B1 and 1B3, OAT1, OAT3, organic cation transporter 2, MATE1, MATE2K, breast cancer resistance protein, multidrug resistance protein 1 and the bile salt export pump. Among the antibiotics/antifungals assessed for potential DDIs, probenecid demonstrated the most potent in vitro inhibition of relebactam uptake; however, such in vitro data did not translate into clinically relevant DDIs, suggesting that relebactam can be co-administered with OAT inhibitors, such as probenecid. CONCLUSIONS: Overall, relebactam has low potential to be a victim or perpetrator of DDIs with major drug transporters.


Asunto(s)
Compuestos de Azabiciclo/farmacocinética , Transporte Biológico , Riñón/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Inhibidores de beta-Lactamasas/farmacocinética , Animales , Línea Celular , Vesículas Extracelulares , Humanos , Modelos Biológicos
2.
J Nurs Meas ; 22(1): 59-76, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24851664

RESUMEN

BACKGROUND AND PURPOSE: The importance of healthy work environments has received attention. Health care organizations are plagued with conflict which is detrimental to work environments. Thus, conflict must be studied. The purpose of this article is to describe the testing of a measure of conflict. METHODS: A survey was used to evaluate the psychometric properties. The sample consisted of 430 nurses at an academic medical center. RESULTS: Using principal component analysis (PCA) with varimax rotation, a six-factor solution (30 items) that explained 74.3% of variance emerged. Coefficient alpha ranged from .95 to .81. Correlations with existing scales supported construct validity (r = -.32(-)-.58). CONCLUSIONS: The results are encouraging. Use of the scale may provide insight into the impact of conflict on patient, staff, and organizational outcomes.


Asunto(s)
Conflicto Psicológico , Procesos de Grupo , Enfermeras y Enfermeros/psicología , Psicometría/métodos , Encuestas y Cuestionarios , Adulto , Femenino , Humanos , Relaciones Interpersonales , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
3.
J Clin Immunol ; 33(2): 397-406, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23054338

RESUMEN

Vancomycin has been shown to affect tumor necrosis factor-alpha (TNF-α) pathways as an immunomodulator; this is thought to be separate from its function as an antibiotic [1]. Previous studies have shown that oral vancomycin (OV) is an effective treatment for concomitant primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) in children [2, 3]. Since both diseases are associated with immune dysfunction, we hypothesized that vancomycin's therapeutic effect in IBD and PSC occurs through immunomodulation. Therefore, we examined the in vivo immunological changes that occur during OV treatment of 14 children with PSC and IBD. Within 3 months of OV administration, peripheral gamma-glutamyl transpeptidase (GGT) and alanine aminotransferase (ALT) concentrations, white blood cell (WBC) counts, and neutrophil counts normalized from elevated levels before treatment. Patients also demonstrated improved biliary imaging studies, liver biopsies and IBD symptoms and biopsies. Additionally, plasma transforming growth factor beta (TGF-ß) levels were increased without concurrent shifts in Th1-or Th2-associated cytokine production. Peripheral levels of CD4 + CD25hiCD127lo and CD4 + FoxP3+ regulatory T (Treg) cells also increased in OV-treated PSC + IBD patients compared to pretreatment levels. A unique case study shows that the therapeutic effects of OV in the treatment of PSC + IBD do not always endure after OV discontinuation, with relapse of PSC associated with a decrease in blood Treg levels; subsequent OV retreatment was then associated with a rise in blood Treg levels and normalization of liver function tests (LFTs). Taken together, these studies support immune-related pathophysiology of PSC with IBD, which is responsive to OV.


Asunto(s)
Colangitis Esclerosante/inmunología , Factores Inmunológicos/farmacología , Enfermedades Inflamatorias del Intestino/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Vancomicina/farmacología , Adolescente , Alanina Transaminasa/sangre , Recuento de Células Sanguíneas , Niño , Preescolar , Colangitis Esclerosante/tratamiento farmacológico , Colangitis Esclerosante/metabolismo , Citocinas/sangre , Femenino , Humanos , Factores Inmunológicos/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Pruebas de Función Hepática , Estudios Longitudinales , Masculino , Resultado del Tratamiento , Vancomicina/uso terapéutico , gamma-Glutamiltransferasa/sangre
4.
Folia Phoniatr Logop ; 65(6): 275-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24820237

RESUMEN

OBJECTIVE: Excessive supraglottic and abnormal fine vibratory characteristics associated with vocal hyperfunction are identified even in individuals with normal laryngeal structure, function and vocal quality when they undergo stroboscopy, possibly due to anxiety. The purpose of this study is to (a) test for vocal hyperfunction in individuals with normal laryngeal structure and function and if present, (b) to track changes in vocal hyperfunction associated with anxiety when stroboscopy is repeated within 24-48 h. PARTICIPANTS AND METHODS: Thirty participants, naïve to stroboscopy, underwent the procedure and completed the State-Trait Anxiety Inventory 3 times over 24-48 h. RESULTS: 41.4% of participants demonstrated vocal hyperfunction in supraglottic and fine vibratory characteristics after the first trial. Vocal hyperfunction decreased to 27.6% after the third trial. RESULTS showed a significant main effect of time indicating that vocal hyperfunction decreased as participants repeated stroboscopy. Although the average anxiety score decreased across trials, state (anxiety) had no significant effect on change in vocal hyperfunction. CONCLUSIONS: In the real world, true representation of vocal function can be achieved by getting a patient acquainted to the presence of strobe in the oral cavity and practice the tasks that will be attempted during the procedure without introducing vocal hyperfunction and most importantly, without the use of a topical anesthetic.


Asunto(s)
Ansiedad/etiología , Estroboscopía/psicología , Calidad de la Voz , Adolescente , Adulto , Femenino , Humanos , Masculino , Educación del Paciente como Asunto , Valores de Referencia , Método Simple Ciego , Estrés Psicológico/etiología , Vibración , Pliegues Vocales/fisiopatología , Trastornos de la Voz/fisiopatología , Adulto Joven
5.
Bioorg Med Chem Lett ; 22(7): 2444-9, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22390835
6.
Bioorg Med Chem Lett ; 21(1): 182-5, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21115245

RESUMEN

A series of 2,4-diphenyl-1H-imidazole analogs have been synthesized and displayed potent human CB2 agonist activity. Many of these analogs showed high functional selectivity over human CB1 receptors. The syntheses, structure-activity relationships, and selected pharmacokinetic data of these analogs are described.


Asunto(s)
Imidazoles/química , Dolor/tratamiento farmacológico , Receptor Cannabinoide CB2/agonistas , Administración Oral , Animales , Enfermedad Crónica , Humanos , Imidazoles/farmacocinética , Imidazoles/uso terapéutico , Ratas , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Relación Estructura-Actividad
7.
Nurs Educ Perspect ; 32(2): 102-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21667791

RESUMEN

With globalization and major immigration flows, intercultural teaching encounters are likely to increase, along with the need to assure intercultural teaching effectiveness.Thus, the purpose of this article is to present a conceptual framework for nurse educators to consider when anticipating an intercultural teaching experience. Kirkpatrick's and Bushnell's models provide a basis for the conceptual framework. Major concepts of the model include input, process, output, and outcome.The model may possibly be used to guide future research to determine which variables are most influential in explaining intercultural teaching effectiveness.


Asunto(s)
Evaluación del Rendimiento de Empleados , Docentes de Enfermería/normas , Personal Profesional Extranjero/normas , Enfermería Transcultural/educación , Habilitación Profesional , Competencia Cultural , Conocimientos, Actitudes y Práctica en Salud , Humanos , Japón
8.
Dysphagia ; 25(2): 112-26, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19495873

RESUMEN

We recently established that the SOD1-G93A transgenic mouse is a suitable model for oral-stage dysphagia in amyotrophic lateral sclerosis (ALS). The purpose of the present study was to determine whether it could serve as a model for pharyngeal-stage dysphagia as well. Electrophysiological and histological experiments were conducted on end-stage SOD1-G93A transgenic mice (n = 9) and age-matched wild-type (WT) littermates (n = 12). Transgenic mice required a twofold higher stimulus frequency (40 Hz) applied to the superior laryngeal nerve (SLN) to evoke swallowing compared with WT controls (20 Hz); transgenic females required a significantly higher (P < 0.05) stimulus frequency applied to the SLN to evoke swallowing compared with transgenic males. Thus, both sexes demonstrated electrophysiological evidence of pharyngeal dysphagia but symptoms were more severe for females. Histological evidence of neurodegeneration (vacuoles) was identified throughout representative motor (nucleus ambiguus) and sensory (nucleus tractus solitarius) components of the pharyngeal stage of swallowing, suggesting that pharyngeal dysphagia in ALS may be attributed to both motor and sensory pathologies. Moreover, the results of this investigation suggest that sensory stimulation approaches may facilitate swallowing function in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/complicaciones , Trastornos de Deglución/etiología , Faringe/patología , Análisis de Varianza , Animales , Trastornos de Deglución/patología , Modelos Animales de Enfermedad , Electromiografía , Femenino , Humanos , Masculino , Ratones , Superóxido Dismutasa/genética
9.
Comput Inform Nurs ; 28(4): 229-34, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20571375

RESUMEN

The purpose of this project was to demonstrate how a hospital clinical database can be utilized to calculate individual nursing unit activities that affect nurses' workload. While research has established that staffing is associated with patient safety, few studies have examined ways to measure nurse workload and its impact on patient safety. The widely used midnight census does not account for the number of patients who occupy a bed in a 24-hour period. In this study, a hospital clinical data repository was used to calculate workload measures such as total treated patients, midnight census, and admission, discharges, and transfers, as well as a unit activity index. Unit activity indexes for intensive care and medical-surgical units were compared over time, by shift, day of week, and month. Admission, discharges, and transfers varied according to unit type. During 1994 to 2006, unit activity index increased. Fluctuations in unit activity index were noted according to shift, day of week, and month. Hospital clinical data repositories can be used to calculate workload measures, and these measures should be incorporated with other traditional measures in making staffing decisions.


Asunto(s)
Recolección de Datos/métodos , Bases de Datos Factuales , Sistemas de Información en Hospital/organización & administración , Personal de Enfermería en Hospital/provisión & distribución , Sistemas de Información para Admisión y Escalafón de Personal/organización & administración , Carga de Trabajo/estadística & datos numéricos , Ocupación de Camas/estadística & datos numéricos , Bases de Datos Factuales/estadística & datos numéricos , Humanos , Evaluación de Necesidades , Investigación en Administración de Enfermería , Admisión del Paciente/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Transferencia de Pacientes/estadística & datos numéricos , Administración de la Seguridad/organización & administración , Estaciones del Año , Sudeste de Estados Unidos , Estudios de Tiempo y Movimiento
10.
Nurs Educ Perspect ; 31(3): 156-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20635619

RESUMEN

This paper reports the results of a survey conducted to explore the perceptions of Japanese graduate nursing students about the teaching performance of an American teacher. The impact of cultural differences on classroom behavior and communication between Japanese graduate nursing students and the American teacher are also explored. Students were enrolled in a nursing education course in the first semester of the graduate program. Data for the analysis were the student opinion surveys, which included Likert scale items and space for narrative responses. Results of the survey are reported as well as the results of a follow-up meeting that was held with the students. The students emphasized the importance of the quality of the interpretation.


Asunto(s)
Diversidad Cultural , Educación de Postgrado en Enfermería , Multilingüismo , Adulto , Humanos , Japón , Persona de Mediana Edad , Estados Unidos
11.
Dysphagia ; 24(2): 180-95, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19107538

RESUMEN

Relatively little is known about the underlying neuropathology of dysphagia in amyotrophic lateral sclerosis (ALS); thus, effective treatments remain elusive. Tremendous progress toward understanding and treating dysphagia in ALS may be possible through the use of an animal model of dysphagia in ALS research; however, no such animal model currently exists. The most logical candidate to consider is the SOD1-G93A transgenic mouse, the most widely investigated animal model of ALS. To investigate whether this animal model develops dysphagia, oral behaviors (lick and mastication rates) of SOD1-G93A transgenic mice (n = 30) were evaluated at three time points based on hind limb motor function: asymptomatic (60 days), disease onset (approximately 110 days), and disease end-stage (approximately 140 days). Age-matched nontransgenic littermates (n = 30) served as controls. At each time point, lick and mastication rates were significantly lower (p < 0.05) for transgenic mice compared with controls. Histologic analysis of the brainstem showed marked neurodegeneration (vacuolation) of the trigeminal and hypoglossal nuclei, two key motor components involved in mastication and licking behaviors. These results demonstrate a clinicopathologic correlation of oral dysfunction in SOD1-G93A transgenic mice, thereby establishing the SOD1-G93A transgenic mouse as a bona fide animal model of oral dysphagia in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/complicaciones , Trastornos de Deglución/etiología , Masticación , Animales , Índice de Masa Corporal , Progresión de la Enfermedad , Conducta Alimentaria , Ratones , Modelos Animales , Superóxido Dismutasa
12.
Toxicol Sci ; 172(1): 155-166, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31406999

RESUMEN

MK-7680, a cyclic nucleotide prodrug, caused significant kidney tubule injury in female rats when administered orally at 1000 mg/kg/day for 2 weeks using 10% Polysorbate 80 as vehicle. However, kidney injury was absent when MK-7680 was administered at the same dose regimen using 100% Polyethylene Glycol 200 (PEG 200) as the vehicle. Subsequent investigations revealed that MK-7680 triphosphate concentrations in kidney were much lower in rats treated with MK-7680 using PEG 200 compared with 10% Polysorbate 80 vehicle, whereas plasma exposures of MK-7680 prodrug were similar. In vitro studies demonstrated that PEG 200 is an inhibitor of human renal uptake transporter organic anion transporter 3 (OAT3), of which MK-7680 is a substrate. Furthermore, PEG 200 and PEG 400 were found to interfere in vitro with human renal transporters OAT3, organic cation transporter (OCT) 2, multidrug resistance-associated protein (MRP) 2 and 4, and multidrug and toxin extrusion protein (MATE) 1 and 2K, but not OAT1. These results support a conclusion that PEG 200 may prevent MK-7680-induced kidney injury by inhibiting its active uptake into proximal tubular cells by OAT3. Caution should be exercised therefore when using PEGs as vehicles for toxicity assessment for compounds that are substrates of renal transporters.

13.
J Pediatr Gastroenterol Nutr ; 47(1): 61-7, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18607270

RESUMEN

BACKGROUND: Primary sclerosing cholangitis is a rare chronic cholestatic condition of unknown etiology, frequently associated with inflammatory bowel disease and characterized by diffuse fibrosing and inflammatory destruction of the intra- and/or extrahepatic biliary duct system. PATIENTS AND METHODS: The study involved 14 children with primary sclerosing cholangitis confirmed by either liver biopsy, endoscopic retrograde cholangiopancreatography, and/or magnetic resonance cholangiogram. In each of the 14 cases, liver histology showed characteristic features consistent with primary sclerosing cholangitis. Eleven children had intrahepatic biliary beading and strictures (6 by endoscopic retrograde cholangiopancreatography; 5 by magnetic resonance cholangiogram). Biochemical tests of liver function including alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase and the erythrocyte sedimentation rate were elevated for a mean 17 +/- 22 months before vancomycin treatment was initiated. All of the patients were shown to have inflammatory bowel disease histologically; 13 of those patients had clinical evidence of colitis. Oral vancomycin was given to all 14 patients. RESULTS: All 14 patients showed improvement in their alanine aminotransferase (P = 0.007), gamma-glutamyl transpeptidase (P = 0.005), erythrocyte sedimentation rate (P = 0.008), and clinical symptoms with oral vancomycin treatment. There was less improvement noted in the patients with cirrhosis when compared with the patients without cirrhosis. CONCLUSIONS: Before this study, there has not been an effective long-term treatment for sclerosing cholangitis to prevent the usual progression of this disease to cirrhosis. This study showed that oral vancomycin could be an effective long-term treatment of sclerosing cholangitis in children, especially those without cirrhosis.


Asunto(s)
Antibacterianos/uso terapéutico , Colangitis Esclerosante/tratamiento farmacológico , Hígado/enzimología , Vancomicina/uso terapéutico , Administración Oral , Adolescente , Alanina Transaminasa/sangre , Sedimentación Sanguínea , Niño , Preescolar , Colangiopancreatografia Retrógrada Endoscópica/métodos , Colangitis Esclerosante/sangre , Colangitis Esclerosante/diagnóstico , Progresión de la Enfermedad , Femenino , Humanos , Inmunosupresores/uso terapéutico , Hígado/fisiología , Cirrosis Hepática/prevención & control , Pruebas de Función Hepática , Masculino , Estudios Prospectivos , Resultado del Tratamiento , gamma-Glutamiltransferasa/sangre
14.
Annu Rev Nurs Res ; 26: 175-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18709750

RESUMEN

The purpose of this chapter is to review the literature on quality of care in rural areas. Keywords related to rural quality of care were used to search CINAHL and MEDLINE databases for articles published between 2005 and 2007 (limited to studies occurring in the United States). The review consisted of a total of 46 articles. Limitations include inconsistent definitions of rural, the use of only articles available to the reviewers, an unclear understanding of the context of many of the studies, and lack of a clear operational definition of quality. The studies were grouped and discussed according to quality of workforce, practice, treatment, interventions, and technology in rural areas. Each study's contribution to the understanding of quality health care in rural areas and to determining what was effective in improving staff, patient, or organizational outcomes in rural areas was considered. This chapter also offers a discussion of ethical issues and data quality in rural research. Issues for future research include a focus on patient safety, mental health issues, and the use of technology to improve quality of care in rural areas. Future research should also focus on demonstration studies of model applications. The nursing profession has a unique opportunity to conduct research that will contribute to the development of knowledge that will ultimately improve the quality of health and health care for individuals in rural communities.


Asunto(s)
Investigación en Enfermería/organización & administración , Calidad de la Atención de Salud/organización & administración , Servicios de Salud Rural/organización & administración , Gestión de la Calidad Total/organización & administración , Atención Ambulatoria , Relaciones Comunidad-Institución , Terapias Complementarias , Recolección de Datos , Planificación en Desastres , Accesibilidad a los Servicios de Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Servicios de Salud Mental , Modelos de Enfermería , Rol de la Enfermera , Proceso de Enfermería , Evaluación de Resultado en la Atención de Salud , Cuidados Paliativos , Proyectos de Investigación , Salud Rural , Población Rural , Administración de la Seguridad , Evaluación de la Tecnología Biomédica , Estados Unidos
15.
J Nurs Educ ; 57(11): 648-654, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30388285

RESUMEN

BACKGROUND: Interpersonal relationships are fundamental to competent delivery of health care. Nursing practice is grounded in interpersonal relationships, making advanced practice registered nurses (APRNs) well prepared to ensure the delivery of safe, effective care. Research demonstrates interpersonal dynamics can be enhanced. Emotional intelligence (EI) is the ability to perceive, understand, manage, and use emotions in self and others, and it comprises a key factor in interpersonal relationships. METHOD: APRN education is grounded in the Quality and Safety Education for Nurses and master's Essentials competencies. This analysis provides a framework to align APRN professional competencies with EI competencies to enhance leadership, communication, and teamwork in health care teams. RESULTS: By using the matrix of EI and APRN competencies provided, nurse educators may implement learning strategies to improve EI and support APRN competencies. CONCLUSION: Well-educated and emotionally intelligent APRNs can enhance cooperation in multidisciplinary teams, promote better communication, and demonstrate APRN leadership to improve patient outcomes. [J Nurs Educ. 2018;57(11):648-654.].


Asunto(s)
Enfermería de Práctica Avanzada/organización & administración , Inteligencia Emocional , Liderazgo , Rol de la Enfermera , Competencia Profesional , Humanos , Relaciones Interprofesionales , Personal de Enfermería en Hospital/organización & administración , Lugar de Trabajo
16.
J Med Chem ; 61(23): 10700-10708, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30388368

RESUMEN

Herein we describe structure-activity relationship (SAR) and metabolite identification (Met-ID) studies that provided insight into the origin of time-dependent inhibition (TDI) of cytochrome P450 3A4 (CYP3A4) by compound 1. Collectively, these efforts revealed that bioactivation of the fluoropyrimidine moiety of 1 led to reactive metabolite formation via oxidative defluorination and was responsible for the observed TDI. We discovered that substitution at both the 4- and 6-positions of the 5-fluoropyrimidine of 1 was necessary to ameliorate this TDI as exemplified by compound 19.


Asunto(s)
Inhibidores del Citocromo P-450 CYP3A/química , Inhibidores del Citocromo P-450 CYP3A/farmacología , Citocromo P-450 CYP3A/metabolismo , Pirimidinas/química , Pirimidinas/farmacología , Animales , Inhibidores del Citocromo P-450 CYP3A/farmacocinética , Humanos , Cinética , Pirimidinas/farmacocinética , Ratas , Relación Estructura-Actividad , Distribución Tisular
17.
ACS Med Chem Lett ; 9(7): 761-767, 2018 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-30034615

RESUMEN

The emergence and evolution of new immunological cancer therapies has sparked a rapidly growing interest in discovering novel pathways to treat cancer. Toward this aim, a novel series of pyrrolidine derivatives (compound 5) were identified as potent inhibitors of ERK1/2 with excellent kinase selectivity and dual mechanism of action but suffered from poor pharmacokinetics (PK). The challenge of PK was overcome by the discovery of a novel 3(S)-thiomethyl pyrrolidine analog 7. Lead optimization through focused structure-activity relationship led to the discovery of a clinical candidate MK-8353 suitable for twice daily oral dosing as a potential new cancer therapeutic.

18.
Nat Chem ; 9(3): 244-249, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28221358

RESUMEN

Strategies for forming liquid dispersions of nanomaterials typically focus on retarding reaggregation, for example via surface modification, as opposed to promoting the thermodynamically driven dissolution common for molecule-sized species. Here we demonstrate the true dissolution of a wide range of important 2D nanomaterials by forming layered material salts that spontaneously dissolve in polar solvents yielding ionic solutions. The benign dissolution advantageously maintains the morphology of the starting material, is stable against reaggregation and can achieve solutions containing exclusively individualized monolayers. Importantly, the charge on the anionic nanosheet solutes is reversible, enables targeted deposition over large areas via electroplating and can initiate novel self-assembly upon drying. Our findings thus reveal a unique solution-like behaviour for 2D materials that enables their scalable production and controlled manipulation.

19.
J Med Chem ; 49(7): 2294-310, 2006 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-16570926

RESUMEN

Melanin-concentrating hormone (MCH) is a cyclic, nonadecapeptide expressed in the CNS of all vertebrates that regulates feeding behavior and energy homeostasis via interaction with the central melanocortin system. Regulation of this interaction results in modulation of food intake and body weight gain, demonstrating significant therapeutic potential for the treatment of obesity. The MCH-1 receptor (MCH-R1) has been identified as a key target in MCH regulation, as small molecule antagonists of MCH-R1 have demonstrated activity in vivo. Herein, we document our research in a bicyclo[3.1.0]hexyl urea series with particular emphasis on structure-activity relationships and optimization of receptor occupancy, measured both in vitro and via an ex vivo binding assay following an oral dosing regimen. Several compounds have been tested in vivo and exhibit oral efficacy in relevant acute rodent feeding models. In particular, 24u has proven efficacious in chronic rodent models of obesity, showing a statistically significant reduction in food intake and body weight over a 28 day study.


Asunto(s)
Fármacos Antiobesidad/síntesis química , Compuestos de Fenilurea/síntesis química , Piperazinas/síntesis química , Receptores de Somatostatina/antagonistas & inhibidores , Urea/análogos & derivados , Urea/síntesis química , Administración Oral , Animales , Fármacos Antiobesidad/farmacología , Disponibilidad Biológica , Peso Corporal/efectos de los fármacos , Encéfalo/metabolismo , Células CHO , Cricetinae , Cricetulus , Ingestión de Alimentos/efectos de los fármacos , Semivida , Masculino , Obesidad/tratamiento farmacológico , Compuestos de Fenilurea/farmacología , Piperazinas/farmacología , Ensayo de Unión Radioligante , Ratas , Receptores de Somatostatina/metabolismo , Relación Estructura-Actividad , Distribución Tisular , Urea/farmacología
20.
Sci Transl Med ; 8(363): 363ra150, 2016 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-27807285

RESUMEN

ß-Amyloid (Aß) peptides are thought to be critically involved in the etiology of Alzheimer's disease (AD). The aspartyl protease ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) is required for the production of Aß, and BACE1 inhibition is thus an attractive target for the treatment of AD. We show that verubecestat (MK-8931) is a potent, selective, structurally unique BACE1 inhibitor that reduced plasma, cerebrospinal fluid (CSF), and brain concentrations of Aß40, Aß42, and sAPPß (a direct product of BACE1 enzymatic activity) after acute and chronic administration to rats and monkeys. Chronic treatment of rats and monkeys with verubecestat achieved exposures >40-fold higher than those being tested in clinical trials in AD patients yet did not elicit many of the adverse effects previously attributed to BACE inhibition, such as reduced nerve myelination, neurodegeneration, altered glucose homeostasis, or hepatotoxicity. Fur hypopigmentation was observed in rabbits and mice but not in monkeys. Single and multiple doses were generally well tolerated and produced reductions in Aß40, Aß42, and sAPPß in the CSF of both healthy human subjects and AD patients. The human data were fit to an amyloid pathway model that provided insight into the Aß pools affected by BACE1 inhibition and guided the choice of doses for subsequent clinical trials.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Péptidos beta-Amiloides/química , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Sistema Nervioso Central/metabolismo , Óxidos S-Cíclicos/farmacología , Tiadiazinas/farmacología , Administración Oral , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Encéfalo/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Diseño de Fármacos , Femenino , Glucosa/metabolismo , Macaca fascicularis , Espectroscopía de Resonancia Magnética , Ratones , Vaina de Mielina/química , Péptidos/química , Conejos , Ratas
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