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Mishra T.,Kadi Sarva Vishwavidyalaya University | Shrivastav P.S.,Gujarat University
The Scientific World Journal | Year: 2014

Objectives. HIV protease inhibitors are used in the treatment of patients suffering from AIDS and they act at the final stage of viral replication by interfering with the HIV protease enzyme. The paper describes a selective, sensitive, and robust method for simultaneous determination of three protease inhibitors atazanavir, darunavir and ritonavir in human plasma by ultra performance liquid chromatography-tandem mass spectrometry. Materials and Methods. The sample pretreatment consisted of solid phase extraction of analytes and their deuterated analogs as internal standards from 50 μL human plasma. Chromatographic separation of analytes was performed on Waters Acquity UPLC C18 (50 × 2.1 mm, 1.7 μm) column under gradient conditions using 10 mM ammonium formate, pH 4.0, and acetonitrile as the mobile phase. Results. The method was established over a concentration range of 5.0-6000 ng/mL for atazanavir, 5.0-5000 ng/mL for darunavir and 1.0-500 ng/mL for ritonavir. Accuracy, precision, matrix effect, recovery, and stability of the analytes were evaluated as per US FDA guidelines. Conclusions. The efficiency of sample preparation, short analysis time, and high selectivity permit simultaneous estimation of these inhibitors. The validated method can be useful in determining plasma concentration of these protease inhibitors for therapeutic drug monitoring and in high throughput clinical studies. © 2014 Tulsidas Mishra and Pranav S. Shrivastav. Source

Awasthi A.K.,Wroclaw University | Sylwester B.,Polish Academy of Sciences | Sylwester J.,Polish Academy of Sciences | Jain R.,Kadi Sarva Vishwavidyalaya University
Astrophysical Journal | Year: 2016

We investigate the evolution of the differential emission measure distribution (DEM[T]) in various phases of a B8.3 flare which occurred on 2009 July 04. We analyze the soft X-ray (SXR) emission in the 1.6-8.0 keV range, recorded collectively by the Solar Photometer in X-rays (SphinX; Polish) and the Solar X-ray Spectrometer (Indian) instruments. We conduct a comparative investigation of the best-fit DEM[T] distributions derived by employing various inversion schemes, namely, single Gaussian, power-law functions and a Withbroe-Sylwester (W-S) maximum likelihood algorithm. In addition, the SXR spectrum in three different energy bands, that is, 1.6-5.0 keV (low), 5.0-8.0 keV (high), and 1.6-8.0 keV (combined), is analyzed to determine the dependence of the best-fit DEM[T] distribution on the selection of the energy interval. The evolution of the DEM[T] distribution, derived using a W-S algorithm, reveals multi-thermal plasma during the rise to the maximum phase of the flare, and isothermal plasma in the post-maximum phase of the flare. The thermal energy content is estimated by considering the flare plasma to be (1) isothermal and (2) multi-thermal in nature. We find that the energy content during the flare, estimated using the multi-thermal approach, is in good agreement with that derived using the isothermal assumption, except during the flare maximum. Furthermore, the (multi-) thermal energy estimated while employing the low-energy band of the SXR spectrum results in higher values than that derived from the combined energy band. On the contrary, the analysis of the high-energy band of the SXR spectrum leads to lower thermal energy than that estimated from the combined energy band. © 2016. The American Astronomical Society. All rights reserved. Source

Shah B.,Kadi Sarva Vishwavidyalaya University | Deshpande S.,Kb Institute Of Pharmaceutical Education And Research
Value in Health Regional Issues | Year: 2014

Objective: To assess the influence of diabetes on health-related quality of life (HRQOL) in patients with coronary artery disease (CAD) and identify predictors of health status at 1-year follow-up after an acute coronary event. Methods: A prospective cohort study in patients diagnosed with CAD at a tertiary care hospital from India. The EuroQol five-dimensional (EQ-5D) questionnaire was administered at 1-year follow-up. Multivariate stepwise liner regression was used to assess predictors of EQ visual analogue scale (VAS) and EQ-5D questionnaire utility scores. Respondents reporting problems on the EQ-5D questionnaire were stratified by the presence of diabetes at baseline for comparison. Results: Of 960 (30% diabetic) patients with CAD enrolled in a main study cohort, 306 (76% males, 21% diabetic) responded to the HRQOL questionnaire at 1 year. Diabetic patients reported more difficulties/problems than did nondiabetic patients for EQ-5D questionnaire dimensions (mobility, 12.3% vs. 4.1%, P = 0.03; usual activities, 56.9% vs. 41.3%, P = 0.03; pain/discomfort, 50.8% vs. 17.8%, P < 0.001; anxiety/depression, 33.8% vs. 14.9%, P < 0.001), except for self-care (12.3% vs. 17.5%, P = 0.35). Mean ± SD EQ VAS and EQ-5D questionnaire utility scores were significantly lower for patients with CAD with diabetes versus those without diabetes (0.75 ± 0.15 vs. 0.83 ± 0.15, P = 0.0002, and 67.8 ± 8.8 vs. 73.6 ± 5.4, P = 0.0001, respectively). Presence of diabetes, use of beta-blockers on discharge, and treatment strategy significantly influenced the VAS score, whereas myocardial infarction as final diagnosis and the presence of prior CHF predicted worse EQ-5D questionnaire utility scores. Conclusions: The poorer HRQOL as assessed by the EQ-5D questionnaire among patients with CAD who had diabetes highlights the need of individualized treatment programs to improve outcomes in this most vulnerable population. © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Source

Gupta A.,Kadi Sarva Vishwavidyalaya University | Gupta A.,Veeda Clinical Research | Singhal P.,Veeda Clinical Research | Shrivastav P.S.,Gujarat University | And 2 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2011

A simple, precise and rapid ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed and validated for the quantification of darunavir, a protease inhibitor, using darunavir-d9 as internal standard (IS). The method involved liquid-liquid extraction of darunavir and IS in methyl- tert-butyl ether from 50. μL human plasma. The chromatographic separation was achieved on an Acquity UPLC BEH C18 (50 mm. ×. 2.1. mm, 1.7. μm particle size) analytical column under gradient conditions, in a run time of 1.6. min. The precursor. →. product ion transitions for darunavir (m/. z 548.1. →. 392.0) and IS (m/. z 557.1. →. 401.0) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) and positive ion mode. The method was extensively validated for its selectivity, sensitivity, carryover check, linearity, precision and accuracy, reinjection reproducibility, recovery, matrix effect, ion suppression/enhancement, stability and dilution integrity. The linearity of the method was established in the concentration range of 1.0-5000 ng/mL. The mean relative recovery for darunavir (100.8%) and IS (89.8%) from spiked plasma samples was consistent and reproducible. The application of this method for routine measurement of plasma darunavir concentration was demonstrated by a bioequivalence study conducted in 40 healthy Indian subjects for a 600 mg tablet formulation along with 100 mg ritonavir as booster under fast and fed conditions. To demonstrate the reproducibility in the measurement of study data, an incurred sample reanalysis was done with 400 subject samples and the % change in concentration was within ±12%. © 2011 Elsevier B.V. Source

Parekh J.M.,Kadi Sarva Vishwavidyalaya University | Sanyal M.,St Xaviers College | Yadav M.,Cadila Pharmaceuticals Ltd | Shrivastav P.S.,Kadi Sarva Vishwavidyalaya University | Shrivastav P.S.,Gujarat University
Bioanalysis | Year: 2013

Background: Iloperidone is a novel antipsychotic drug with high affinity for serotonin and D2 dopamine receptors. A sensitive and rapid isotope dilution LC-MS/MS method has been developed for the simultaneous determination of iloperidone and its two major metabolites in human plasma. Results: The analytes and their deuterated analogs as internal standards were quantitatively extracted from 100-μl human plasma by SPE. The method was validated over the concentration range of 0.01-6 ng/ml for all the analytes. Baseline separation of analytes was possible within 3 min on ACE 5 C8 column. The accuracy and precision (%CV) of the method varied from 96.2 to 105%, and 1.17 to 4.75%, respectively. The extraction recovery was >84%, while the internal standard-normalized matrix factors ranged from 0.97-1.03 for all three analytes. Conclusion: The developed method was successfully applied to support a bioequivalence study in healthy volunteers. © 2013 Future Science Ltd. Source

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