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1.
Am J Gastroenterol ; 117(6): 902-917, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35442220

RESUMEN

INTRODUCTION: Evidence about specific carbohydrate diet (SCD) for inflammatory bowel disease (IBD) is limited. We conducted 54 single-subject, double-crossover N-of-1 trials comparing SCD with a modified SCD (MSCD) and comparing each with the participant's baseline, usual diet (UD). METHODS: Across 19 sites, we recruited patients aged 7-18 years with IBD and active inflammation. Following a 2-week baseline (UD), patients were randomized to 1 of 2 sequences of 4 alternating 8-week SCD and MSCD periods. Outcomes included fecal calprotectin and patient-reported symptoms. We report posterior probabilities from Bayesian models comparing diets. RESULTS: Twenty-one (39%) participants completed the trial, 9 (17%) completed a single crossover, and 24 (44%) withdrew. Withdrawal or early completion occurred commonly (lack of response [n = 11], adverse events [n = 11], and not desiring to continue [n = 6]). SCD and MSCD performed similarly for most individuals. On average, there was <1% probability of a clinically meaningful difference in IBD symptoms between SCD and MSCD. The average treatment difference was -0.3 (95% credible interval -1.2, 0.75). There was no significant difference in the ratio of fecal calprotectin geometric means comparing SCD and MSCD (0.77, 95% credible interval 0.51, 1.10). Some individuals had improvement in symptoms and fecal calprotectin compared with their UD, whereas others did not. DISCUSSION: SCD and MSCD did not consistently improve symptoms or inflammation, although some individuals may have benefited. However, there are inherent difficulties in examining dietary changes that complicate study design and ultimately conclusions regarding effectiveness.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Complejo de Antígeno L1 de Leucocito , Adolescente , Teorema de Bayes , Niño , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/dietoterapia , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/dietoterapia , Dieta , Heces/química , Humanos , Inflamación/complicaciones , Inflamación/dietoterapia , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/dietoterapia , Complejo de Antígeno L1 de Leucocito/análisis , Medicina de Precisión
2.
Hum Genet ; 139(9): 1173-1182, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31729547

RESUMEN

With advances in medical care, many women with genetic conditions previously known to decrease life expectancy are reaching childbearing age. Thus, it is important to understand the management of patients in the preconception, antepartum, and postpartum periods as they pose a unique challenge to the obstetrician. Most rare disorders lack well-established clinical guidelines for management in pregnancy. Existing data stem from case reports, case series, and expert opinion. We aim to summarize these recommendations and develop a clinical reference for managing reproductive age women with these conditions. We review recommendations for women with inborn errors in metabolism, connective tissue disorders, skeletal dysplasia, and selected single gene disorders. In all cases, it is crucial to employ a multidisciplinary team to optimize care for patients with rare disease before, during, and immediately after their pregnancies. The emphasis on expert consensus recommendations in the guidance of obstetric care is a signal that more studies are needed to determine best practices.


Asunto(s)
Enfermedades Genéticas Congénitas/genética , Diagnóstico Preimplantación/métodos , Diagnóstico Prenatal/métodos , Femenino , Fertilización In Vitro , Humanos , Lactante , Esperanza de Vida , Madres , Embarazo
3.
J Pharmacokinet Pharmacodyn ; 47(5): 473-484, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32647957

RESUMEN

To develop a framework for evaluating the resorption effects of Cathepsin K (CatK) inhibitors and to inform dose regimen selection, a pharmacokinetic/pharmacodynamic (PK/PD) model for odanacatib (ODN) was developed based upon data from Phase 1 studies. Pooled PK/PD data from 11 studies (N = 249) were fit reasonably to a population inhibitory sigmoid Emax model. Body weight on E0 (baseline uNTx/Cr, urinary N-terminal telopeptide normalized by creatinine) and age on Emax (fractional inhibition of the biomarker response) were significant covariates for biomarker response. Simulations of typical osteoporosis patients (by age, sex and weight) indicated minimal differences between sexes in concentration-uNTx/Cr relationship. There was no evidence that regimen (daily vs. weekly dosing) influenced the PK/PD relationship of resorption inhibition for odanacatib. PK/PD models based on data from odanacatib (ODN) Phase 1 studies demonstrated that uNTx/Cr was an appropriate bone resorption biomarker for assessment of the effects of a CatK inhibitor. The models also identified the determinants of response in the PK/PD relationship for ODN (body weight on E0 and age on Emax).


Asunto(s)
Compuestos de Bifenilo/farmacocinética , Conservadores de la Densidad Ósea/farmacocinética , Resorción Ósea/prevención & control , Catepsina K/antagonistas & inhibidores , Adulto , Anciano , Biomarcadores/orina , Compuestos de Bifenilo/administración & dosificación , Compuestos de Bifenilo/efectos adversos , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Resorción Ósea/diagnóstico , Resorción Ósea/orina , Catepsina K/metabolismo , Creatinina/orina , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Monitoreo de Drogas/métodos , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/orina , Procolágeno/orina , Resultado del Tratamiento , Adulto Joven
4.
Br J Clin Pharmacol ; 85(6): 1072-1083, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30663085

RESUMEN

Cathepsin K (CatK) is a cysteine protease abundantly expressed by osteoclasts and localized in the lysosomes and resorption lacunae of these cells. CatK is the principal enzyme responsible for the degradation of bone collagen. Odanacatib is a selective, reversible inhibitor of CatK at subnanomolar potency. The pharmacokinetics of odanacatib have been extensively studied and are similar in young healthy men, postmenopausal women and elderly men, and were qualitatively similar throughout Phase 1 development and in-patient studies. Following 3 weeks of 50 mg once weekly dosing the geometric mean area under the curve from 0 to 168 hours was 41.1 µM h, the concentration at 168 hours was 126 nM and the harmonic mean apparent terminal half-life was 84.8 hr. Odanacatib exposure increased in a less than dose proportional manner due to solubility limited absorption. It is estimated that approximately 70% of the absorbed dose of odanacatib is eliminated via metabolism, 20% is excreted as unchanged drug in the bile or faeces, and 10% is excreted as unchanged drug in the urine. The systemic clearance was low (approximately 13 mL/min). Odanacatib decreases the degradation of bone matrix proteins and reduces the efficiency of bone resorption with target engagement confirmed by a robust decrease in serum C-telopeptides of type 1 collagen (approximately 60%), urinary aminoterminal crosslinked telopeptides of type 1 collagen to creatinine ratio (approximately 50%) and total urine deoxypyridinoline/Cr (approximately 30%), with an increase in serum cross-linked carboxy-terminal telopeptide of type 1 collagen (approximately 55%). The 50-mg weekly dosing regimen evaluated in Phase 3 achieved near maximal reduction in bone resorption throughout the treatment period. The extensive clinical programme for odanacatib, together with more limited clinical experience with other CatK inhibitors (balicatib and ONO-5334), provides important insights into the clinical pharmacology of CatK inhibition and the potential role of CatK in bone turnover and mineral homeostasis. Key findings include the ability of this mechanism to: (i) provide sustained reductions in resorption markers, increases in bone mineral density, and demonstrated fracture risk reduction; (ii) be associated with relative formation-sparing effects such that sustained resorption reduction is achieved without accompanying meaningful reductions in bone formation; and (iii) lead to increases in osteoclast number as well as other osteoclast activity (including build-up of CatK enzyme), which may yield transient increases in resorption following treatment discontinuation and the potential for nonmonotonic responses at subtherapeutic doses.


Asunto(s)
Compuestos de Bifenilo/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Remodelación Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Catepsina K/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/uso terapéutico , Osteoporosis/tratamiento farmacológico , Animales , Compuestos de Bifenilo/efectos adversos , Compuestos de Bifenilo/farmacocinética , Conservadores de la Densidad Ósea/efectos adversos , Conservadores de la Densidad Ósea/farmacocinética , Huesos/enzimología , Huesos/fisiopatología , Catepsina K/metabolismo , Inhibidores de Cisteína Proteinasa/efectos adversos , Inhibidores de Cisteína Proteinasa/farmacocinética , Femenino , Humanos , Masculino , Osteoporosis/enzimología , Osteoporosis/patología , Transducción de Señal , Investigación Biomédica Traslacional , Resultado del Tratamiento
5.
Australas Psychiatry ; 27(1): 41-43, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30488716

RESUMEN

OBJECTIVES:: This article draws attention to an initiative aimed at benefiting colleagues in developing countries, through financial and/or moral support. It describes an attempt to engage The Royal College of Australian and New Zealand Psychiatrists ('the College') in supporting this philanthropic activity. It further aims to attract interest from the College and fellows in contributing to international philanthropy. CONCLUSIONS:: Doubling provides a credible model for facilitating better mental health care in situations where there are trained staff but inadequate resources. The College's resistance to engagement with this project may represent a missed opportunity for philanthropic support.


Asunto(s)
Países en Desarrollo , Salud Global , Cooperación Internacional , Salud Mental , Psiquiatría , Sociedades Médicas , Australia , Humanos , Nueva Zelanda
6.
J Pharmacol Exp Ther ; 365(3): 507-518, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29563326

RESUMEN

The abnormal accumulation of amyloid-ß (Aß) in the brain parenchyma has been posited as a central event in the pathophysiology of Alzheimer's disease. Recently, we have proposed a systems pharmacology model of the amyloid precursor protein (APP) pathway, describing the Aß APP metabolite responses (Aß40, Aß42, sAPPα, and sAPPß) to ß-secretase 1 (BACE1) inhibition. In this investigation this model was challenged to describe Aß dynamics following γ-secretase (GS) inhibition. This led an extended systems pharmacology model, with separate descriptions to characterize the sequential cleavage steps of APP by BACE1 and GS, to describe the differences in Aß response to their respective inhibition. Following GS inhibition, a lower Aß40 formation rate constant was observed, compared with BACE1 inhibition. Both BACE1 and GS inhibition were predicted to lower Aß oligomer levels. Further model refinement and new data may be helpful to fully understand the difference in Aß dynamics following BACE1 versus GS inhibition.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Modelos Biológicos , Proteolisis , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Animales , Inhibidores Enzimáticos/farmacología , Macaca mulatta , Proteolisis/efectos de los fármacos
7.
Plant Physiol ; 172(2): 889-900, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27506241

RESUMEN

Sphingolipid synthesis is tightly regulated in eukaryotes. This regulation in plants ensures sufficient sphingolipids to support growth while limiting the accumulation of sphingolipid metabolites that induce programmed cell death. Serine palmitoyltransferase (SPT) catalyzes the first step in sphingolipid biosynthesis and is considered the primary sphingolipid homeostatic regulatory point. In this report, Arabidopsis (Arabidopsis thaliana) putative SPT regulatory proteins, orosomucoid-like proteins AtORM1 and AtORM2, were found to interact physically with Arabidopsis SPT and to suppress SPT activity when coexpressed with Arabidopsis SPT subunits long-chain base1 (LCB1) and LCB2 and the small subunit of SPT in a yeast (Saccharomyces cerevisiae) SPT-deficient mutant. Consistent with a role in SPT suppression, AtORM1 and AtORM2 overexpression lines displayed increased resistance to the programmed cell death-inducing mycotoxin fumonisin B1, with an accompanying reduced accumulation of LCBs and C16 fatty acid-containing ceramides relative to wild-type plants. Conversely, RNA interference (RNAi) suppression lines of AtORM1 and AtORM2 displayed increased sensitivity to fumonisin B1 and an accompanying strong increase in LCBs and C16 fatty acid-containing ceramides relative to wild-type plants. Overexpression lines also were found to have reduced activity of the class I ceramide synthase that uses C16 fatty acid acyl-coenzyme A and dihydroxy LCB substrates but increased activity of class II ceramide synthases that use very-long-chain fatty acyl-coenzyme A and trihydroxy LCB substrates. RNAi suppression lines, in contrast, displayed increased class I ceramide synthase activity but reduced class II ceramide synthase activity. These findings indicate that ORM mediation of SPT activity differentially regulates functionally distinct ceramide synthase activities as part of a broader sphingolipid homeostatic regulatory network.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Homeostasis , Oxidorreductasas/metabolismo , Serina C-Palmitoiltransferasa/metabolismo , Esfingolípidos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Mutación , Oxidorreductasas/genética , Plantas Modificadas Genéticamente , Unión Proteica , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serina C-Palmitoiltransferasa/genética
8.
Matern Child Health J ; 21(7): 1469-1478, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28155023

RESUMEN

Objectives To examine clinical and demographic characteristics associated with availability of self-reported and measured pre-pregnancy weight, differences in these parameters, and characteristics associated with self-report accuracy. Methods Retrospective cohort of 7483 women who delivered at a large academic medical center between 2011 and 2014. Measured pre-pregnancy weights recorded within a year of conception and self-reported pre-pregnancy weights reported anytime during pregnancy were abstracted from electronic medical records. Difference in weights was calculated as self-reported minus measured pre-pregnancy weight. Logistic and linear regression models estimated associations between demographic and clinical characteristics, and presence of self-reported and measured weights, and weight differences. Results 42.2% of women had both self-reported and measured pre-pregnancy weight, 49.7% had only self-reported, and 2.8% had only measured. Compared to white women, black women and women of other races/ethnicities were less likely to have self-reported weight, and black, Asian, and Hispanic women, and women of other races/ethnicities were less likely to have measured weights. For 85%, pre-pregnancy BMI categorized by self-reported and measured weights were concordant. Primiparas and multiparas were more likely to underreport their weight compared to nulliparas (b = -1.32 lbs, 95% CI -2.24 to -0.41 lbs and b = -2.74 lbs, 95% CI -3.82 to -1.67 lbs, respectively). Discussion Utilization of self-reported or measured pre-pregnancy weight for pre-pregnancy BMI classification results in identical categorization for the majority of women. Providers may wish to account for underreporting for patients with a BMI close to category cutoff by recommending a range of gestational weight gain that falls within recommendations for both categories where feasible.


Asunto(s)
Índice de Masa Corporal , Peso Corporal , Complicaciones del Embarazo/epidemiología , Atención Prenatal/métodos , Aumento de Peso , Adulto , Pueblo Asiatico , Consejo , Femenino , Hispánicos o Latinos , Humanos , Massachusetts , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Factores de Riesgo , Autoinforme , Población Blanca
9.
J Pharmacokinet Pharmacodyn ; 44(5): 403-414, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28573468

RESUMEN

Pembrolizumab is a monoclonal antibody that targets the programmed death-1 receptor to induce immune-mediated clearance (CL) of tumor cells. Originally approved by the US Food and Drug Administration in 2014 for treating patients with unresectable or metastatic melanoma, pembrolizumab is now also used to treat patients with non-small-cell lung cancer, classical Hodgkin lymphoma, head and neck cancer, and urothelial cancer. This paper describes the recently identified feature of pembrolizumab pharmacokinetics, the time-dependent or time-varying CL. Overall results indicate that CL decreases over the treatment period of a typical patient in a pattern well described by a sigmoidal function of time with three parameters: the maximum proportion change in CL from baseline (approximately Imax or exactly eImax - 1), the time to reach Imax/2 (TI50), and a Hill coefficient. Best overall response per response evaluation criteria in solid tumor category was found to be associated with the magnitude of Imax.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacocinética , Antineoplásicos/farmacocinética , Ensayos Clínicos como Asunto/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/sangre , Antineoplásicos/sangre , Carcinoma de Pulmón de Células no Pequeñas/sangre , Femenino , Humanos , Masculino , Melanoma/sangre , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
10.
J Pharmacol Exp Ther ; 357(1): 205-16, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26826190

RESUMEN

The deposition of amyloid-ß (Aß) oligomers in brain parenchyma has been implicated in the pathophysiology of Alzheimer's disease. Here we present a systems pharmacology model describing the changes in the amyloid precursor protein (APP) pathway after administration of three different doses (10, 30, and 125 mg/kg) of the ß-secretase 1 (BACE1) inhibitor MBi-5 in cisterna magna ported rhesus monkeys. The time course of the MBi-5 concentration in plasma and cerebrospinal fluid (CSF) was analyzed in conjunction with the effect on the concentrations of the APP metabolites Aß42, Aß40, soluble ß-amyloid precursor protein (sAPP) α, and sAPPß in CSF. The systems pharmacology model contained expressions to describe the production, elimination, and brain-to-CSF transport for the APP metabolites. Upon administration of MBi-5, a dose-dependent increase of the metabolite sAPPα and dose-dependent decreases of sAPPß and Aß were observed. Maximal inhibition of BACE1 was close to 100% and the IC50 value was 0.0256 µM (95% confidence interval, 0.0137-0.0375). A differential effect of BACE1 inhibition on Aß40 and Aß42 was observed, with the Aß40 response being larger than the Aß42 response. This enabled the identification of an Aß42 oligomer pool in the systems pharmacology model. These findings indicate that decreases in monomeric Aß responses resulting from BACE1 inhibition are partially compensated by dissociation of Aß oligomers and suggest that BACE1 inhibition may also reduce the putatively neurotoxic oligomer pool.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/efectos de los fármacos , Precursor de Proteína beta-Amiloide/metabolismo , Fragmentos de Péptidos/metabolismo , Algoritmos , Péptidos beta-Amiloides/efectos de los fármacos , Animales , Biotransformación , Química Encefálica/efectos de los fármacos , Cisterna Magna , Relación Dosis-Respuesta a Droga , Inyecciones , Macaca mulatta , Masculino , Modelos Estadísticos , Fragmentos de Péptidos/efectos de los fármacos
11.
Drug Metab Dispos ; 44(9): 1450-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27402726

RESUMEN

A stable-label i.v./oral study design was conducted to investigate the pharmacokinetics (PK) of odanacatib. Healthy, postmenopausal women received oral doses of unlabeled odanacatib administered simultaneously with a reference of 1 mg i.v. stable (13)C-labeled odanacatib. The absolute bioavailability of odanacatib was 30% at 50 mg (the phase 3 dose) and 70% at 10 mg, which is consistent with solubility-limited absorption. Odanacatib exposure (area under the curve from zero to infinity) increased by 15% and 63% when 50 mg was administered with low-fat and high-fat meals, respectively. This magnitude of the food effect is unlikely to be clinically important. The volume of distribution was ∼100 liters. The clearance was ∼0.8 l/h (13 ml/min), supporting that odanacatib is a low-extraction ratio drug. Population PK modeling indicated that 88% of individuals had completed absorption of >80% bioavailable drug within 24 hours, with modest additional absorption after 24 hours and periodic fluctuations in plasma concentrations contributing to late values for time to Cmax in some subjects.


Asunto(s)
Compuestos de Bifenilo/farmacocinética , Interacciones Alimento-Droga , Posmenopausia , Administración Oral , Anciano , Área Bajo la Curva , Disponibilidad Biológica , Compuestos de Bifenilo/administración & dosificación , Compuestos de Bifenilo/sangre , Estudios Cruzados , Femenino , Semivida , Humanos , Infusiones Intravenosas , Persona de Mediana Edad
12.
Plant Cell ; 25(11): 4627-39, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24214397

RESUMEN

Maintenance of sphingolipid homeostasis is critical for cell growth and programmed cell death (PCD). Serine palmitoyltransferase (SPT), composed of LCB1 and LCB2 subunits, catalyzes the primary regulatory point for sphingolipid synthesis. Small subunits of SPT (ssSPT) that strongly stimulate SPT activity have been identified in mammals, but the role of ssSPT in eukaryotic cells is unclear. Candidate Arabidopsis thaliana ssSPTs, ssSPTa and ssSPTb, were identified and characterized. Expression of these 56-amino acid polypeptides in a Saccharomyces cerevisiae SPT null mutant stimulated SPT activity from the Arabidopsis LCB1/LCB2 heterodimer by >100-fold through physical interaction with LCB1/LCB2. ssSPTa transcripts were more enriched in all organs and >400-fold more abundant in pollen than ssSPTb transcripts. Accordingly, homozygous ssSPTa T-DNA mutants were not recoverable, and 50% nonviable pollen was detected in heterozygous ssspta mutants. Pollen viability was recovered by expression of wild-type ssSPTa or ssSPTb under control of the ssSPTa promoter, indicating ssSPTa and ssSPTb functional redundancy. SPT activity and sensitivity to the PCD-inducing mycotoxin fumonisin B1 (FB1) were increased by ssSPTa overexpression. Conversely, SPT activity and FB1 sensitivity were reduced in ssSPTa RNA interference lines. These results demonstrate that ssSPTs are essential for male gametophytes, are important for FB1 sensitivity, and limit sphingolipid synthesis in planta.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Micotoxinas/farmacología , Serina C-Palmitoiltransferasa/metabolismo , Esfingolípidos/biosíntesis , Secuencia de Aminoácidos , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Muerte Celular/efectos de los fármacos , ADN Bacteriano , Fumonisinas/farmacología , Datos de Secuencia Molecular , Mutación , Filogenia , Plantas Modificadas Genéticamente , Polen/genética , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/genética , Serina C-Palmitoiltransferasa/genética , Especificidad por Sustrato
14.
J Aging Soc Policy ; 27(1): 21-46, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25299976

RESUMEN

State Medicaid programs have expanded home and community-based services (HCBS). This article compares trends and variations in state policies for Medicaid HCBS programs in 2005 and 2010. State limitations on financial eligibility criteria and service benefits have remained stable. Although the use of consumer direction, independent providers, and family care providers has increased, some states do not have these options. The increased adoption of state cost control policies have led to large increases in persons on waiver wait lists. Access could be improved by standardizing and liberalizing state HCBS policies, but state fiscal concerns are barriers to rebalancing between HCBS and institutional services.


Asunto(s)
Medicaid , Gobierno Estatal , Anciano , Anciano de 80 o más Años , Servicios de Salud Comunitaria/economía , Control de Costos/tendencias , Determinación de la Elegibilidad/métodos , Accesibilidad a los Servicios de Salud/tendencias , Servicios de Atención de Salud a Domicilio/economía , Servicios de Atención de Salud a Domicilio/tendencias , Humanos , Medicaid/economía , Medicaid/legislación & jurisprudencia , Medicaid/tendencias , Estados Unidos
15.
Clin Transl Sci ; 17(2): e13732, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38593352

RESUMEN

Molnupiravir is an oral prodrug of the broadly active, antiviral ribonucleoside analog N-hydroxycytidine (NHC). The primary circulating metabolite NHC is taken up into cells and phosphorylated to NHC-triphosphate (NHC-TP). NHC-TP serves as a competitive substrate for viral RNA-dependent RNA polymerase (RdRp), which results in an accumulation of errors in the viral genome, rendering virus replication incompetent. Molnupiravir has demonstrated activity against SARS-CoV-2 both clinically and preclinically and has a high barrier to development of viral resistance. Little to no molnupiravir is observed in plasma due to rapid hydrolysis to NHC. Maximum concentrations of NHC are reached at 1.5 h following administration in a fasted state. The effective half-life of NHC is 3.3 h, reflecting minimal accumulation in the plasma following twice-daily (Q12H) dosing. The terminal half-life of NHC is 20.6 h. NHC-TP exhibits a flatter profile with a lower peak-to-trough ratio compared with NHC, which supports Q12H dosing. Renal and hepatic pathways are not major routes of elimination, as NHC is primarily cleared by metabolism to uridine and cytidine, which then mix with the endogenous nucleotide pools. In a phase III study of nonhospitalized patients with COVID-19 (MOVe-OUT), 5 days of treatment with 800 mg molnupiravir Q12H significantly reduced the incidence of hospitalization or death compared with placebo. Patients treated with molnupiravir also had a greater reduction in SARS-CoV-2 viral load and improved clinical outcomes, compared with those receiving placebo. The clinical effectiveness of molnupiravir has been further demonstrated in several real-world evidence studies. Molnupiravir is currently authorized or approved in more than 25 countries.


Asunto(s)
Citidina/análogos & derivados , Ribonucleósidos , Ciencia Traslacional Biomédica , Humanos , Citidina/farmacología , Hidroxilaminas , SARS-CoV-2
16.
Planta ; 237(1): 55-64, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22983672

RESUMEN

The constitutive and drought-induced activities of the Arabidopsis thaliana RD29A and RD29B promoters were monitored in soybean (Glycine max (L.) Merr.] via fusions with the visual marker gene ß-glucuronidase (GUS). Physiological responses of soybean plants were monitored over 9 days of water deprivation under greenhouse conditions. Data were used to select appropriate time points to monitor the activities of the respective promoter elements. Qualitative and quantitative assays for GUS expression were conducted in root and leaf tissues, from plants under well-watered and dry-down conditions. Both RD29A and RD29B promoters were significantly activated in soybean plants subjected to dry-down conditions. However, a low level of constitutive promoter activity was also observed in both root and leaves of plants under well-watered conditions. GUS expression was notably higher in roots than in leaves. These observations suggest that the respective drought-responsive regulatory elements present in the RD29X promoters may be useful in controlling targeted transgenes to mitigate abiotic stress in soybean, provided the transgene under control of these promoters does not invoke agronomic penalties with leaky expression when no abiotic stress is imposed.


Asunto(s)
Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Glycine max/genética , Regiones Promotoras Genéticas/genética , Agua/farmacología , Southern Blotting , Sequías , Fluorometría , Glucuronidasa/genética , Glucuronidasa/metabolismo , Histocitoquímica , Plantas Modificadas Genéticamente , Glycine max/metabolismo
17.
Br J Clin Pharmacol ; 75(5): 1240-54, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23013236

RESUMEN

AIMS: To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of odanacatib (ODN), a cathepsin K inhibitor, in humans. METHODS: Two double-blind, randomized, placebo-controlled, single oral dose studies were performed with ODN (2-600 mg) in 44 healthy volunteers (36 men and eight postmenopausal women). RESULTS: Adverse experiences (AEs) with single doses of ODN were transient and mild to moderate, with the exception of one severe AE of gastroenteritis. Headache was the most frequent AE. After absorption of ODN (initial peak concentrations 4-6 h postdose), plasma concentrations exhibited a monophasic decline, with an apparent terminal half-life of ∼40-80 h. The area under the curve0-24 hours (AUC(0-24 h)), concentration at 24 hours (C(24 h)) and maximum concentration (C(max,overal)) increased in a less than dose-proportional manner from 2 to 600 mg. Administration of ODN with a high-fat meal led to ∼100% increases in AUC(0-24 h), C(max,day1), C(max,overall) and C(24 h) relative to the fasted state, while administration with a low-fat meal led to a ∼30% increase in those parameters. Reduction of biomarkers of bone resorption, the C- and N-telopeptides of cross-links of type I collagen, (CTx and NTx, respectively), was noted at 24 h for doses ≥5 mg and at 168 h postdose for ≥10 mg. In postmenopausal women administered 50 mg ODN, reductions in serum CTx of -66% and urine NTx/creatinine (uNTx/Cr) of -51% relative to placebo were observed at 24 h. At 168 h, reductions in serum CTx (-70%) and uNTx/Cr (-78%) were observed relative to baseline. Pharmacokinetic/pharmacodynamic modeling characterized the ODN concentration/uNTx/Cr relation, with a modeled EC50 value of 43.8 nM and ∼80% maximal reduction. CONCLUSIONS: Odanacatib was well tolerated and has a pharmacokinetic and pharmacodynamic profile suitable for once weekly dosing.


Asunto(s)
Compuestos de Bifenilo/farmacología , Catepsina K/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Osteoporosis/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Compuestos de Bifenilo/efectos adversos , Compuestos de Bifenilo/farmacocinética , Resorción Ósea/metabolismo , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Femenino , Semivida , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/metabolismo , Adulto Joven
18.
Br J Clin Pharmacol ; 76(6): 917-31, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23594227

RESUMEN

AIMS: To characterize pharmacokinetic parameters of MK-0916 and its safety and tolerability in lean, healthy male subjects following single and multiple oral doses. To assess (by stable-isotope labelling) the in vivo inhibition of cortisone-to-cortisol conversion following oral MK-0916. METHODS: Data are presented from two randomized, controlled, double-blind, rising-dose phase I studies. In the first study, subjects received single oral doses of 0.4-100 mg MK-0916 (n = 16). In the second study, subjects received 0.2-225 mg MK-0916 followed by daily doses of 0.2-100 mg for 13 days beginning on day 2 or day 15 (n = 80). Plasma and urine drug concentrations were measured for pharmacokinetic analysis. For pharmacodynamic analysis, concentrations of plasma [(13)C4]cortisol were measured by high-pressure liquid chromatography and tandem mass spectrometry following a single oral dose of 5 mg [(13)C4]cortisone. RESULTS: Doses ≥3 mg were rapidly absorbed (time at which maximal concentration was achieved in plasma, 1.1-1.8 h). Exposure (measured as the area under the concentration-time curve from 0 to 168 h) increased approximately in proportion to dose. Values for the maximal plasma concentration and the plasma concentration at 24 h increased in excess of dose proportionality at doses <6 mg and roughly in proportion to dose at doses >6 mg. In subjects dosed with 6 mg MK-0916 once daily for 14 days, the mean trough plasma concentration was 240 nm and in vivo cortisone-to-cortisol conversion was inhibited by 84%. The relationship between plasma MK-0916 and hepatic 11ß-hydroxysteroid dehydrogenase type 1 inhibition was well represented by a simple Emax model with an IC50 of 70.4 nm. Exposure to MK-0916 was generally well tolerated. CONCLUSIONS: These findings indicate that 11ß-hydroxysteroid dehydrogenase type 1 is effectively inhibited in human subjects by doses of MK-0916 that are well tolerated.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/farmacocinética , Triazoles/farmacología , Triazoles/farmacocinética , Adolescente , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/efectos adversos , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Triazoles/administración & dosificación , Triazoles/efectos adversos , Adulto Joven
19.
Am J Obstet Gynecol MFM ; 5(4): 100881, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36724813

RESUMEN

BACKGROUND: An abnormally soft cervix could contribute to the pathophysiology of cervical shortening and cervical insufficiency. Multiple techniques to measure cervical softness have been developed but none are used routinely in clinical practice. A clinically acceptable technique to measure cervical softness could improve identification of patients at risk for cervix-related preterm birth. OBJECTIVE: This study aimed to measure cervical softness in patients with cervical insufficiency and in normal controls using a novel, aspiration-based device. We hypothesized that the cervix is softer in patients with cervical insufficiency. STUDY DESIGN: This was a cross-sectional study of patients presenting for cerclage at a single academic medical center. Cervical softness was measured using a noninvasive, aspiration-based device placed on the anterior lip of the cervix during a speculum examination. The device measured the aspiration pressure required to displace cervical tissue to a predefined deformation level. Stiff tissue required increased aspiration pressure, whereas soft tissue required lower pressure values. Cerclage patients were subdivided into 3 groups, namely history-indicated, ultrasound-indicated, and examination-indicated cerclage. Controls were healthy volunteers between 12+0 weeks and 23+6 weeks of gestation without a history of cervical insufficiency and were matched by gestational age to the patients in the cerclage groups. Women with a cerclage in place, multiple gestations, active genital infection, or previous cervical excision procedures were excluded. Delivery information was subsequently recorded as well. RESULTS: Data from 133 women were analyzed; of those, 54 patients were in the cerclage group (23 history-indicated, 12 ultrasound-indicated, and 19 examination-indicated participants) and 79 were controls (40 in the first trimester and 39 in the second trimester groups). Patients who presented for ultrasound-indicated cerclage had significantly softer cervices (median; interquartile range) than second trimester controls (62 mbar; 50.5-114 vs 81 mbar; 75-101; P=.042). The difference in cervical softness was not significantly different between the history-indicated and examination-indicated cerclage groups and their respective control groups. CONCLUSION: Patients presenting for ultrasound-indicated cerclage had significantly softer cervices than normal controls as measured by an aspiration-based device. Quantitative measurement of cervical softness with the aspiration-based device is a promising technique for objective measurement of cervical softness during pregnancy.


Asunto(s)
Cerclaje Cervical , Cuello del Útero , Nacimiento Prematuro , Femenino , Humanos , Recién Nacido , Embarazo , Estudios de Casos y Controles , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/cirugía , Estudios Transversales , Nacimiento Prematuro/diagnóstico , Nacimiento Prematuro/etiología , Nacimiento Prematuro/prevención & control , Ultrasonografía Prenatal , Adulto
20.
Clin Pharmacol Ther ; 113(6): 1337-1345, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37017631

RESUMEN

Molnupiravir (MOV) is an oral antiviral for the treatment of coronavirus disease 2019 (COVID-19) in outpatient settings. This analysis investigated the relationship between ß-D-N4-hydroxycytidine (NHC) pharmacokinetics and clinical outcomes in patients with mild to moderate COVID-19 in the phase III part of the randomized, double-blind, placebo-controlled MOVe-OUT trial. Logistic regression models of the dependency of outcomes on exposures and covariates were constructed using a multistep process. Influential covariates were identified first using placebo arm data, followed by assessment of exposure-dependency in drug effect using data from both the placebo and MOV arms. The exposure-response (E-R) analysis included 1,313 participants; 630 received MOV and 683 received placebo. Baseline viral load, baseline disease severity, age, weight, viral clade, active cancer, and diabetes were identified as significant determinants of response using placebo data. Absolute measures of viral load on days 5 and 10 were strong on-treatment predictors of hospitalization. An additive area under the curve (AUC)-based maximum effect (Emax ) model with a fixed Hill coefficient of 1 best represented the exposure-dependency in drug effect and the AUC50 was estimated to be 19,900 nM hour. Patients at 800 mg achieved near maximal response, which was larger than for 200 or 400 mg. The final E-R model was externally validated and predicted that the relative reduction in hospitalization with MOV treatment would vary with patient characteristics and factors in the population. In conclusion, the E-R results support the MOV dose of 800 mg twice daily to treat COVID-19. Many patient characteristics and factors impacted outcomes beyond drug exposures.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Hidroxilaminas , Citidina , Antivirales/efectos adversos
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