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91.
BACKGROUND: Fluticasone furoate (drug code GW685698) is an enhanced-affinity glucocorticoid that has been developed for the treatment of allergic rhinitis. OBJECTIVES: The objectives of this study were to estimate the absolute bioavailability of fluticasone furoate nasal spray and to describe the intranasal (IN) and IV pharmacokinetics of fluticasone furoate in healthy subjects. METHODS: This was a single-center, randomized, open label, 2-period crossover study. Healthy male and female subjects were randomized to receive supra-therapeutic doses of fluticasone furoate 880 microg IN qSh for 10 doses in 1 treatment period, and a single IV dose of 250 pg fluticasone furoate given as an infusion over 20 minutes in the other treatment period. Each treatment period was separated by a 4- to 5-day washout period. Blood sampling was carried out over 8 hours following the final IN dose and 24 hours following the IV dose to determine plasma fluticasone furoate concentrations. Plasma samples were analyzed for fluticasone furoate using online solid-phase extraction with high-performance liquid chromatography with tandem mass-spectrometric detection. The lower limit of quantification was 10 pg/mL. The sample size was based primarily on logistical considerations. Sample-size sensitivity was assessed by estimating the 90% CI for the absolute bioavailability of IN fluticasone furoate, based on different estimated bioavailabilities and within-subject SDs. The following pharmacokinetic parameters were derived: IN administration: AUC from time 0 to the end of the dosing interval (AUC(0-tau)), AUC(0-t), C(max), and T(max); IV administration: AUC(0-infinity), AUC(0-t), t(1/2), C(max), T(max), total systemic clearance, and volume of distribution at steady state. RESULTS: A total of 16 subjects were included in the study. Their mean age was 27.8 years (range, 19-45 years), and their mean body weight was 72.84 kg (range, 55.3-97.2 kg). The geometric mean AUC(0-tau) for 880 microg IN was 74.9 pg x mL/h and geometric mean AUC(0-infinity) for 250 microg IV was 4259 pg x mL/h. The geometric mean of the absolute bioavailability of fluticasone furoate nasal spray in these healthy subjects was 0.50% (90% CI, 0.34%-0.74%). The administration of large doses by the IN route did not elicit clinical concern. Three (19%) of 16 subjects reported adverse events (AEs) during the IN administration period, with 2 subjects experiencing dizziness and 1, toothache. Five (31%) subjects reported AEs during the IV administration period, with 3 subjects experiencing infusion-site or IV catheter-related events; 1 subject, dizziness; and 1 subject, headache. CONCLUSIONS: The geometric mean of the absolute bioavailability of fluticasone furoate 880 microg IN qSh for 10 doses in these healthy subjects was low--0.50%.  相似文献   
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Neurosurgical Review - Neuropathic pain presents a burdening and impairing condition which may occasionally occur after spinal tumor surgery. While it has been described in peripheral nerve sheath...  相似文献   
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This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of various doses of the anti‐CD40 monoclonal antibody bleselumab (ASKP1240) in de novo kidney transplant recipients receiving concomitant standard immunosuppression over 90 days posttransplant. Transplant recipients were randomized (1:1:1:1:1) to bleselumab 50 mg, 100 mg, 200 mg, or 500 mg, or placebo, in addition to standard maintenance immunosuppression. The primary pharmacokinetic endpoints were AUCinf, Cmax, and AUClast. The primary pharmacodynamic endpoint was B cell CD40 receptor occupancy over time. Overall, 50 kidney transplant recipients were randomized; 45 received their randomized treatment (bleselumab [n = 37] or placebo [n = 8]). AUCinf and AUClast demonstrated a more than dose‐proportional increase in the range of 50‐500 mg, and Cmax increased linearly with increasing dose. Maximal receptor occupancy for B cell CD40 was reached at all dose levels and was prolonged as dose increased. No kidney transplant recipients experienced cytokine release syndrome or a thromboembolic event. Treatment‐emergent anti‐bleselumab antibodies were found in one kidney transplant recipient in the bleselumab 50 mg group; these were detected only at Day 7. Overall, bleselumab demonstrated nonlinear pharmacokinetics and dose‐dependent prolonged B cell CD40 receptor occupancy and was well tolerated at all doses (ClinicalTrials.gov: NCT01279538).  相似文献   
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The purpose of this study was to test hypothesized relationships of the health promotion model (HPM) as a means of predicting moderate‐to‐vigorous physical activity (MVPA) among urban, adolescent girls. A secondary analysis of baseline data from a group randomized controlled trial was conducted. The study involved eight urban schools in the Midwestern United States. The sample included girls (N = 517) in the 5th–8th grades. Data were collected on age, body mass index, pubertal status, enjoyment, self‐efficacy, social support, options for physical activity (PA), and commitment to PA. MVPA was measured via accelerometers worn by the girls for 7 days. Structural equation modeling was used to analyze study aims. Mean age of the sample was 11.8 years (standard deviation [SD] = 1.0). Girls attained an average of 3.0 (SD = 1.2) minutes per hour of MVPA. Self‐efficacy had a positive direct (β = .337; p < .001) and total effect (β = .310; p < .001) on MVPA. Social support and options for PA were not significant predictors of commitment to PA or MVPA. Commitment to PA had a negative but nonsignificant effect (β = ?.056; p = .357) on MVPA. The model predicted 10.1% of the variance in MVPA with 9.6% of the variance predicted by self‐efficacy. Limitations include lack of longitudinal analysis and inability to generalize the results to other populations such as boys. PA self‐efficacy continues to emerge as a significant predictor of MVPA in the HPM. Continued theory testing is needed to better understand the correlates and determinants of PA among adolescent girls before designing theory‐based interventions to promote PA.  相似文献   
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OBJECTIVES: We describe how paid and unpaid home care hours received by older unmarried Americans change in response to disability dynamics. We test whether responses to disability declines and improvements are symmetric; that is, we test whether reductions in care hours that are due to disability improvements are of similar magnitude to increases in care hours that are due to disability declines. METHODS: Using a national sample of older unmarried Americans, we examine changes in total hours, paid hours, and unpaid hours of care in response to declines and improvements in personal care (activities of daily living, or ADLs) and routine care (instrumental ADLs, or IADLs) disability. We model changes in the total hours of care received in the past month and jointly model changes in unpaid and paid hours, using Tobit models. RESULTS: Changes in the total hours of care received respond to both increases and decreases in the count of ADL limitations and appear close to symmetric. In contrast, responses to IADL disability dynamics appear to be far less symmetric: Although increases in the count of IADL limitations are met with substantial increases in the total hours of care, decreases are not met with correspondingly large declines in care. The same general pattern is found for unpaid and paid care, and for Medicaid-funded home care. DISCUSSION: Disability and care are not static constructs in old age. Older unmarried persons experience worsening, stabilizing, and recovery of function, and their care hours change accordingly. Evaluations of home care programs must be cognizant of such dynamic realities.  相似文献   
99.

Objectives

The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.

Background

There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.

Methods

Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.

Results

A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: ?8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.

Conclusions

Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927)  相似文献   
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