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1.
Eur J Pharm Sci ; 161: 105806, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33722733

ABSTRACT

A present investigation aimed for multivariate modeling as a solution to resolve inaccuracy in dissolution testing experienced in the use of in-situ UV fiber optics dissolution systems (FODS) due to signal saturation problems. This problem is specifically encountered with high absorbance of moderate to high dose formulations. A high absorbance not only impede a real-time assessment but can also result in inaccurate dissolution profiles. Full spectra (F) and low absorbance regions (L) were employed to develop linear and quadratic (Q) partial least squares (PLS) and principal component regression (PCR) models. The conventional dissolution of atenolol, ibuprofen, and metformin HCl immediate-release (IR) tablets followed by HPLC analysis was used as a reference method to gauge multivariate models' performance in the 'built-in' Opt-Diss model. The linear multivariate modeling outputs resulted in accurate dissolution profiles, despite the potentially high UV signal saturation at later time points. Conversely, the 'built-in' Opt-Diss model and multivariate quadratic models failed to predict dissolution profiles accurately. The current studies show a good agreement in the predictions across both low absorbance region and full spectra, demonstrating the multivariate models' robust predictability. Overall, linear PLS and PCR models showed statistically similar results, which demonstrated their applicative flexibility for using FODS despite signal saturation and provides a unique alternative to traditional and labor-intensive UV or HPLC dissolution testing.


Subject(s)
Ibuprofen , Drug Compounding , Least-Squares Analysis , Solubility , Tablets
2.
AAPS PharmSciTech ; 14(3): 1012-24, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23797303

ABSTRACT

The aim of this investigation was to develop and evaluate freeze-dried mannosylated liposomes for the targeted delivery of selenium. Dipalmitoylphosphatidylcholine, distearoylphosphatidylglycerol, and cholesterol were dissolved in a chloroform and methanol mixture and allowed to form a thin film within a rotatory evaporator. This thin film was hydrated with a sodium selenite (5.8 µM) solution to form multilamellar vesicles and homogenized under high pressure to yield unilamellar nanoliposomes. Se-loaded nanoliposomes were mannosylated by 0.1% w/v mannosamine (Man-Lip-Se) prior to being lyophilized. Mannosamine concentration was optimized with cellular uptake studies in M receptor expressing cells. Non-lyophilized and lyophilized Man-Lip-Se were characterized for size, zeta potential, and entrapment efficiency. The influence of liposomal composition on the characteristics of Man-Lip-Se were evaluated using acidic and basic medium for 24 h. Thermal analysis and powder X-ray diffraction were used to determine the interaction of components within the Man-Lip-Se. The size, zeta potential and entrapment efficiency of the optimum Man-Lip-Se were observed to be 158 ± 28.9 nm, 33.21 ± 0.89 mV, and 77.27 ± 2.34%, respectively. An in vitro Se release of 70-75% up to 24 h in PBS pH 6.8 and <8% Se release in acidic media (0.1 N HCl) in 1 h was observed. The Man-Lip-Se were found to withstand gastric-like environments and showed sustained release. Stable freeze-dried Man-Lip-Se were successfully formulated with a size of <200 nm, ≈ 75% entrapment, and achieved controlled release of Se with stability under acidic media, which may be of importance in the targeted delivery of Se to the immune system.


Subject(s)
Freeze Drying , Liposomes , Mannose/chemistry , Nanostructures , Selenium/chemistry , Animals , Cells, Cultured , Mice , Powder Diffraction , Spectrophotometry, Ultraviolet
3.
J Nutr ; 139(9): 1783S-7S, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19625701

ABSTRACT

As described in this Supplement and elsewhere, consumption of grapes or grape products has been associated with various health benefits. Resveratrol is a unique component of grapes. Following our report on potential cancer chemopreventive activity, thousands of studies have been performed to characterize the mode of action of this substance. Nonetheless, scores of additional chemicals are known to be constituents of grapes, several of which are capable of mediating biological responses. Accordingly, when considering grapes and health, a holistic view appears to be more meaningful, taking into account all chemical components, metabolism, biological potential, biodistribution, absorption, processing, etc. To fathom such a massive amount of information, we propose the creation of focused ontologies. Grapes seem reasonable as a test bed for exploring this approach, especially because a fair amount of results are available with whole-grape powder. In essence, by utilizing a next generation intelligent system, attempts can be made to leverage the existing complexity. This approach involves bringing together all available information, together with expert judgment, and processing this information through a computational "engine" or engines to provide suggested solutions (or implicit functional relationships). Accomplishment of this task, employing grapes as a prototype, could lead to broader application by incorporating the myriad of features associated with other fruits and vegetables. The ability to correlate heretofore-uncharacterized "signatures" with biologic outcome could fundamentally transform copious amounts of disparate information into a coherent explanation of human disease prevention.


Subject(s)
Phytotherapy , Plant Preparations/pharmacology , Vitis/chemistry , Drug Synergism , Fruit/chemistry , Health Promotion , Humans , Plant Preparations/chemistry , Plant Preparations/therapeutic use , Resveratrol , Stilbenes/chemistry , Stilbenes/pharmacology , Stilbenes/therapeutic use
4.
Lancet ; 366(9481): 211-7, 2005.
Article in English | MEDLINE | ID: mdl-16023511

ABSTRACT

BACKGROUND: Data from a pilot study suggested that noetic therapies-healing practices that are not mediated by tangible elements-can reduce preprocedural distress and might affect outcomes in patients undergoing percutaneous coronary intervention. We undertook a multicentre, prospective trial of two such practices: intercessory prayer and music, imagery, and touch (MIT) therapy. METHODS: 748 patients undergoing percutaneous coronary intervention or elective catheterisation in nine USA centres were assigned in a 2x2 factorial randomisation either off-site prayer by established congregations of various religions or no off-site prayer (double-blinded) and MIT therapy or none (unmasked). The primary endpoint was combined in-hospital major adverse cardiovascular events and 6-month readmission or death. Prespecified secondary endpoints were 6-month major adverse cardiovascular events, 6 month death or readmission, and 6-month mortality. FINDINGS: 371 patients were assigned prayer and 377 no prayer; 374 were assigned MIT therapy and 374 no MIT therapy. The factorial distribution was: standard care only, 192; prayer only, 182; MIT therapy only, 185; and both prayer and MIT therapy, 189. No significant difference was found for the primary composite endpoint in any treatment comparison. Mortality at 6 months was lower with MIT therapy than with no MIT therapy (hazard ratio 0.35 (95% CI 0.15-0.82, p=0.016). INTERPRETATION: Neither masked prayer nor MIT therapy significantly improved clinical outcome after elective catheterisation or percutaneous coronary intervention.


Subject(s)
Angioplasty, Balloon, Coronary , Coronary Disease/therapy , Mind-Body Therapies , Spiritual Therapies , Aged , Cardiac Catheterization , Cardiovascular Diseases/mortality , Coronary Disease/psychology , Double-Blind Method , Female , Humans , Imagery, Psychotherapy , Male , Middle Aged , Music , Recurrence , Therapeutic Touch , Treatment Outcome
5.
Cardiol Rev ; 11(6): 309-17, 2003.
Article in English | MEDLINE | ID: mdl-14580299

ABSTRACT

We studied the relationship between mood and mood shift immediately before percutaneous coronary intervention (PCI) and 3 end points: total ischemic burden during PCI, adverse cardiac end points (ACE) after PCI, and death by 6-month follow up. Patients (n = 119) with unstable angina or myocardial infarction completed a visual analog scale (VAS) twice before PCI; before and after a session of stress relaxation, imagery, or touch; or approximately 30 minutes apart for patients assigned to prayer or to standard care. VAS included happiness, satisfaction, calm, hope, worry, shortness of breath, fear, and sadness. We observed a significant correlation between higher hope score before PCI and lower ischemic burden. Patients who experienced ACE had significantly lower hope and happiness scores than those who did not. Patients who survived to 6 months had significantly greater increases in worry and in hope. Our data suggest correlations between simple mood assessments before PCI and clinical outcomes during and after the procedure. More study is needed to understand whether attempts to alter patient mood can affect clinical outcomes.


Subject(s)
Angina, Unstable/psychology , Angioplasty, Balloon, Coronary/psychology , Myocardial Infarction/psychology , Aged , Angina, Unstable/therapy , Female , Humans , Male , Middle Aged , Myocardial Infarction/therapy , Pain Measurement , Retrospective Studies , Treatment Outcome
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