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941.
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943.
944.
The present study was aimed at investigating the effect of hydrotrope and surfactant on poor solubility of atorvastatin calcium. Excipients screening followed by factorial design was performed to study effect of excipients and manufacturing methods on solubility of drug. Three independent factors (carrier, surfactant and manufacturing method) were evaluated at two levels using solubility as a dependant variable. Solid-state characterisation was performed using Fourier transform infrared spectroscopy and differential scanning calorimetry. Optimised complex were incorporated into orally disintegrating micro tablets and in vitro dissolution test was performed. Nicotinamide, Plasdone and sodium dodecyl sulphate were emerged as promising excipients from excipient screening. General regression analysis revealed only the type of carrier has significantly enhanced (P<0.05) the solubility of drug while other factors were found to be nonsignificant. Ratio optimisation trial revealed that drug to nicotinamide ratio is more critical in enhancing the solubility of drug (40 fold increases in solubility compared to pure drug) in comparison to drug-surfactant ratio; however the presence of surfactant deemed essential. Significantly higher rate and extent of dissolution was observed from solid dispersion complex and tablets compared to dissolution of pure drug (P<0.05). Study revealed hydrotrope and surfactant have synergistic effect on solubility and dissolution of atorvastatin calcium and this can be explored further. 相似文献
945.
Nidhi S. Patel Falguni B. Tandel Yogita D. Patel Kartavya B. Thakkar 《Indian journal of pharmaceutical sciences》2014,76(6):535-540
A stability-indicating reverse phase high performance liquid chromatography method was developed and validated for cefixime and linezolid. The wavelength selected for quantitation was 276 nm. The method has been validated for linearity, accuracy, precision, robustness, limit of detection and limit of quantitation. Linearity was observed in the concentration range of 2-12 μg/ml for cefixime and 6-36 μg/ml for linezolid. For RP-HPLC, the separation was achieved by Phenomenex Luna C18 (250×4.6 mm) 5 μm column using phosphate buffer (pH 7):methanol (60:40 v/v) as mobile phase with flow rate 1 ml/min. The retention time of cefixime and linezolid were found to be 3.127 min and 11.986 min, respectively. During force degradation, drug product was exposed to hydrolysis (acid and base hydrolysis), H2O2, thermal degradation and photo degradation. The % degradation was found to be 10 to 20% for both cefixime and linezolid in the given condition. The method specifically estimates both the drugs in presence of all the degradants generated during forced degradation study. The developed methods were simple, specific and economic, which can be used for simultaneous estimation of cefixime and linezolid in tablet dosage form. 相似文献
946.
Stuart Richer Shana Patel Shivani Sockanathan Lawrence J. Ulanski II Luke Miller Carla Podella 《Nutrients》2014,6(10):4404-4420
Background: Longevinex® (L/RV) is a low dose hormetic over-the-counter (OTC) oral resveratrol (RV) based matrix of red wine solids, vitamin D3 and inositol hexaphosphate (IP6) with established bioavailability, safety, and short-term efficacy against the earliest signs of human atherosclerosis, murine cardiac reperfusion injury, clinical retinal neovascularization, and stem cell survival. We previously reported our short-term findings for dry and wet age-related macular degeneration (AMD) patients. Today we report long term (two to three year) clinical efficacy. Methods: We treated three patients including a patient with an AMD treatment resistant variant (polypoidal retinal vasculature disease). We evaluated two clinical measures of ocular structure (fundus autofluorescent imaging and spectral domain optical coherence extended depth choroidal imaging) and qualitatively appraised changes in macular pigment volume. We further evaluated three clinical measures of visual function (Snellen visual acuity, contrast sensitivity, and glare recovery to a cone photo-stress stimulus). Results: We observed broad bilateral improvements in ocular structure and function over a long time period, opposite to what might be expected due to aging and the natural progression of the patient’s pathophysiology. No side effects were observed. Conclusions: These three cases demonstrate that application of epigenetics has long-term efficacy against AMD retinal disease, when the retinal specialist has exhausted other therapeutic modalities. 相似文献
947.
Srinivas Ganta Amit Singh Niravkumar R. Patel Joseph Cacaccio Yashesh H. Rawal Barbara J. Davis Mansoor M. Amiji Timothy P. Coleman 《Pharmaceutical research》2014,31(9):2490-2502
Purpose
Platinum-based chemotherapy is the treatment of choice for malignant epithelial ovarian cancers, but generalized toxicity and platinum resistance limits its use. Theranostic nanoemulsion with a novel platinum prodrug, myrisplatin, and the pro-apoptotic agent, C6-ceramide, were designed to overcome these limitations.Methods
The nanoemulsions, including ones with an EGFR binding peptide and gadolinium, were made using generally regarded as safe grade excipients and a high shear microfluidization process. Efficacy was evaluated in ovarian cancer cells, SKOV3, A2780 and A2780CP.Results
The nanoemulsion with particle size <150 nm were stable in plasma and parenteral fluids for 24 h. Ovarian cancer cells in vitro efficiently took up the non-targeted and EGFR-targeted nanoemulsions; improved cytotoxicity was observed for the these nanoemulsions with the latter showing a 50-fold drop in the IC50 in SKOV3 cells as compared to cisplatin alone. The addition of gadolinium did not affect cell viability in vitro, but showed relaxation times comparable to Magnevist®.Conclusion
The myrisplatin/C6-ceramide nanoemulsion synergistically enhanced in vitro cytotoxicity. An EGFR binding peptide addition further increased in vitro cytotoxicity in EGFR positive cancer cells. The diagnostic version showed MR imaging similar to the clinically relevant Magnevist® and may be suitable as a theranostic for ovarian cancer. 相似文献948.
Lucio R. Volino Rolee Pathak Das Rupal Patel Mansukhani Leon E. Cosler 《American journal of pharmaceutical education》2014,78(9)
Objective. To evaluate the impact of counseling in a simulated medication adherence activity.Design. Students were randomized into 2 groups: patient medication monograph only (PMMO) and patient medication monograph with counseling (PMMC). Both groups received a fictitious medication and monograph. Additionally, the PMMC group received brief counseling. A multiple-choice, paper-based survey instrument was used to evaluate simulated food-drug interactions, adherence, and perceptions regarding the activity’s value and impact on understanding adherence challenges.Assessment. Ninety-two students participated (PMMC, n=45; and PMMO, n=47). Overall, a significantly higher incidence of simulated food-drug interactions occurred in the PMMO group (30%) vs the PMMC group (22%) (p=0.02). Doses taken without simulated food-drug interactions were comparable: 46.2% (PMCC) vs 41.9% (PMMO) (p=0.19). The average number of missed doses were 3.2 (PMMC) vs 2.8 (PMMO) (p=0.55). Approximately 70% of the students found the activity to be valuable and 89% believed it helped them better understand adherence challenges.Conclusion. This activity demonstrated the challenges and important role of counseling in medication adherence. 相似文献
949.
Proietti Riccardo Dowd Rory Gee Lim Ven Yusuf Shamil Panikker Sandeep Hayat Sajad Osman Faizel Patel Kiran Salim Handi Aldhoon Bashar Foster Will Merghani Ahmed Kuehl Michael Banerjee Prithwish Lellouche Nicolas Dhanjal Tarvinder 《Journal of interventional cardiac electrophysiology》2021,62(3):519-529
Journal of Interventional Cardiac Electrophysiology - Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia... 相似文献
950.
Natale Andrea Monir George Patel Anshul M. Fishel Robert S. Marchlinski Francis E. Delaughter M. Craig Athill Charles A. Melby Daniel P. Gonzalez Mario D. Hariharan Ramesh Gidney Brett Tan Tiffany Chinitz Larry A. 《Journal of interventional cardiac electrophysiology》2021,61(1):63-69
Journal of Interventional Cardiac Electrophysiology - The prospective, multicenter SMART SF trial demonstrated the acute safety and effectiveness of the 56-hole porous tip irrigated contact force... 相似文献