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Greg A Kossena William N Charman Ben J Boyd Christopher J H Porter 《Journal of controlled release》2004,99(2):217-229
The existence of a novel cubic liquid crystalline phase is described within the pseudo-ternary system comprising lauric acid, monolaurin, and simulated endogenous intestinal fluid (SEIF). This phase behaviour has been characterized using cross-polarizing light microscopy (CPLM), and the structure of the cubic phase identified by small angle X-ray scattering (SAXS). The presence of the cubic phase was found to be temperature sensitive within the 20-37 degrees C range making it putative material for in situ gelation purposes. The cubic phase was shown to have a high capacity to solubilise a model poorly water-soluble drug, cinnarizine, and initial in vitro release data highlight the potential of this phase to provide sustained release. Absorption of cinnarizine from the cubic phase was studied in an unconscious rat model via duodenal administration and blood sampling via the carotid artery. The rate of absorption was significantly reduced when compared to a simple suspension formulation, a likely combination of retarded erosion of the cubic phase together with hindered drug release from the cubic matrix. The results of this study suggest that this cubic phase may potentially be of benefit in the delivery of poorly water-soluble compounds due to its high loading capacity and potential for sustained release. The ability to manipulate this system using temperature may warrant further interest in delivery applications via other routes of administration. 相似文献
15.
Pudendal nerve palsy is a reported complication of hip arthroscopy. We report a technique using a deflated taped beanbag rather than a perineal post. The patient is placed in the supine or lateral position on a fracture table. The beanbag is contoured around the patient’s flank and thorax. The distal aspect of the beanbag is placed no further than the iliac crest, and care is taken to avoid compression of the posterior aspect of the axillary region or the posterior humerus. The molded beanbag is deflated, a blanket is positioned over the abdomen and lower thorax, and with the use of 3-in-wide cloth tape, the patient and beanbag are secured to the operative table circumferentially. The superior margin of the deflated beanbag remains firm, preventing compression of the thorax and avoiding compromised ventilation. The arm on the operative side is placed across the chest and secured to avoid obstruction of the operative field. This patient positioning provides sufficient stability for adequate traction and good visualization while minimizing the risk of a pudendal nerve palsy. 相似文献
16.
Cardiomyopathy: a late complication of hemolytic uremic syndrome 总被引:2,自引:0,他引:2
Amanda M. Walker Lee N. Benson Greg J. Wilson Gerald S. Arbus 《Pediatric nephrology (Berlin, Germany)》1997,11(2):221-222
This report describes a child who presented with classic hemolytic uremic syndrome (HUS) and 4 months later developed a life-threatening
but reversible cardiomyopathy with global cardiac dysfunction and a left ventricular ejection fraction of 14%. There was no
evidence of electrolyte abnormalities, anemia, hypertension, severe fluid overload, or viral infection. Endomyocardial biopsies
were consistent with a dilated cardiomyopathy. This paper highlights the importance of considering the diagnosis of associated
cardiomyopathy when presenting with late-onset edema following HUS.
Received February 12, 1996; received in revised form and accepted August 22, 1996 相似文献
17.
Elizabeth A Johnson Todd S Harwell Peg M Donahue M'liss A Weisner Michael J McInerney Greg S Holzman Steven D Helgerson 《The Journal of rural health》2003,19(4):506-510
CONTEXT: Vaccine-preventable diseases among adults are major contributing causes of morbidity and mortality in the United States. However, adult immunizations continue to be underutilized in both urban and rural areas. PURPOSE: To evaluate the effectiveness of a community-wide education campaign and mailed reminders promoting pneumococcal immunizations to rural Medicare beneficiaries. METHODS: We implemented a community-wide education campaign, and mailed reminders were sent to Medicare beneficiaries in 1 media market in Montana to increase pneumococcal immunizations. In a second distinct media market, mailed reminders only were sent to beneficiaries. FINDINGS: The proportion of respondents aged 65 years and older aware of pneumococcal immunizations increased significantly from baseline to follow-up among respondents both in the education-plus-reminder (63% to 78%, P = 0.04) and the reminder-only (64% to 74%, P = 0.05) markets. Overall from 1998 to 1999, there was a 3.7-percentage-point increase in pneumococcal immunization claims for Medicare beneficiaries in the education-plus-reminder market and a 1.5-percentage-point increase in the reminder-only market. Medicare beneficiaries sent reminders in the education-plus-reminder market compared to those in the reminder-only market were more likely to have a claim for pneumococcal immunization in 1999 (odds ratio 1.18, 95% confidence interval 1.08 to 1.28). The results suggest that these quality improvement strategies (community education plus reminders and reminders alone) modestly increased pneumococcal immunization awareness and pneumococcal immunization among rural adults. Mailed reminder exposure was associated with an increased prevalence of pneumococcal immunizations between 1998 and 1999 and was augmented somewhat by the education campaign. 相似文献
18.
Levodopa improves physical fatigue in Parkinson's disease: a double-blind, placebo-controlled, crossover study. 总被引:1,自引:0,他引:1
Jau-Shin Lou Greg Kearns Theodore Benice Barry Oken Gary Sexton John Nutt 《Movement disorders》2003,18(10):1108-1114
We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation. 相似文献
19.
The addition of candesartan cilexetil (Atacand®, Amias®, Biopress®, Kenzen®, Ratacand®) to standard therapy for chronic heart failure (CHF) provided important clinical benefits at little or no additional cost in France, Germany, and the UK, according to a detailed economic analysis focusing on major cardiovascular events and prospectively collected resource-use data from the CHARM-Added and CHARM-Alternative trials in patients with CHF and left ventricular (LV) systolic dysfunction. Results of a corresponding cost-effectiveness analysis showed that candesartan cilexetil was either dominant over placebo or was associated with small incremental costs per life-year gained, depending on the country and whether individual trial or pooled data were used. Preliminary data from a US cost-effectiveness analysis based on CHARM data also showed favorable results for candesartan cilexetil.Two cost-effectiveness analyses of candesartan cilexetil in hypertension have been published, both conducted in Sweden. Data from the SCOPE trial in elderly patients with hypertension, which showed a significant reduction in nonfatal stroke with candesartan cilexetil-based therapy versus non-candesartan cilexetil-based treatment, were incorporated into a Markov model and an incremental cost-effectiveness ratio of €12 824 per quality-adjusted life-year (QALY) gained was calculated (2001 value). Another modelled cost-effectiveness analysis of candesartan cilexetil was based on the ALPINE trial, in which the incidence of new-onset diabetes was significantly lower in patients with newly diagnosed hypertension who were randomized to candesartan cilexetil (with or without felodipine) than among those who received hydrochlorothiazide (with or without atenolol). Although candesartan cilexetil was dominant over hydrochlorothiazide, the ALPINE cost-effectiveness analysis relied on a small number of clinical events and did not evaluate the incremental cost of candesartan cilexetil per life-year or QALY gained.In conclusion, despite some inherent limitations, economic analyses incorporating CHARM data and conducted primarily in Europe have shown that candesartan cilexetil appears to be cost effective when added to standard CHF treatment in patients with CHF and compromized LV systolic function. The use of candesartan cilexetil as part of antihypertensive therapy in elderly patients with elevated blood pressure was also deemed to be cost effective in a Swedish analysis, primarily resulting from a reduced risk of nonfatal stroke (as shown in the SCOPE study); however, the generalizability of results to other contexts has not been established. Cost-effectiveness analyses comparing candesartan cilexetil with ACE inhibitors or other angiotensin receptor blockers in CHF or hypertension are lacking, and results reported for candesartan cilexetil in a Swedish economic analysis of ALPINE data focusing on outcomes for diabetes require confirmation and extension. 相似文献
20.
Greg Reynolds Martin Wilson Andrew Peet Theodoros N Arvanitis 《Magnetic resonance in medicine》2006,56(6):1211-1219
The quantitation of metabolite concentrations from in vitro NMR spectra is hampered by the sensitivity of peak positions to experimental conditions. The quantitation methods currently available are generally labor intensive and cannot readily be automated. Here, an algorithm is presented for the automatic time domain analysis of high-resolution NMR spectra. The TARQUIN algorithm uses a set of basis functions obtained by quantum mechanical simulation using predetermined parameters. Each basis function is optimized by subdividing it into a set of signals from magnetically equivalent spins and varying the simulated chemical shifts of each of these groups to match the signal undergoing analysis. A novel approach to the standard multidimensional minimization problem is introduced based on evaluating the fit resulting from different permutations of possible chemical shifts, obtained from one-dimensional searches. Results are presented from the analysis of (1)H proton magic angle spinning spectra of cell lines illustrating the robustness of the method in a typical application. Simulation was used to investigate the biggest peak shifts that can be tolerated. 相似文献