An error occurred while sending the email. Please try again.

Proceed reservation?

Hits per page: 5   10   20   50   100
9465031 hits in 0.869 seconds
 1 PAPER CURRENT Liquid Chromatography-High Resolution Mass Spectrometry for Peptide Drug Quality Control (2015) Publication Date: 2015-02-28 Description: Abstract A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed using three peptide drugs: salmon calcitonin, bivalirudin, and exenatide as model systems to assess the suitability of this approach for monitoring peptide drug product quality. Calcitonin and its related impurities displayed linear responses over the range from 0.1 to 10 μM (R 2 values for calcitonin salmon, Glu14-calcitonin, and acetyl-calcitonin were 0.995, 0.996, and 0.993, respectively). Intra-assay precision in terms of relative standard deviation (%RSD) was less than 10% at all tested concentrations. The accuracy of the method was greater than 85% as measured by spiking 0.1, 0.3, and 1% of Glu14-calcitonin and acetyl-calcitonin into a stock calcitonin solution. Limits of detection for calcitonin, Glu14-calcitonin, and acetyl-calcitonin were 0.02, 0.03, and 0.04 μM, respectively, indicating that an impurity present at less than 0.1% (0.1 μM) of the drug product API concentration (107 μM) could be detected. Method validation studies analyzing bivalirudin and exenatide drug products exhibited similar results to calcitonin salmon in regard to high selectivity, sensitivity, precision, and linearity. Added benefits of using LC-HRMS-based methods are the ability to also determine amino acid composition, confirm peptide sequence, and quantify impurities, even when they are co-eluting, within a single experiment. LC-HRMS represents a promising approach for the quality control of peptides including the measurement of any peptide-related impurities. While the development work performed here is focus on peptide drug products, the principles could be adapted to peptide drug substance. Electronic ISSN: 1550-7416 Topics: Chemistry and Pharmacology Published by Springer on behalf of The American Association of Pharmaceutical Scientists (AAPS). 2 PAPER CURRENT Pharmacodynamic Studies to Demonstrate Bioequivalence of Oral Inhalation Products (2015) Publication Date: 2015-02-28 Description: Abstract In the session on “Pharmacodynamic studies to demonstrate efficacy and safety”, presentations were made on methods of evaluating airway deposition of inhaled corticosteroids and bronchodilators, and systemic exposure indirectly using pharmacodynamic study designs. For inhaled corticosteroids, limitations of measuring exhaled nitric oxide and airway responsiveness to adenosine for anti-inflammatory effects were identified, whilst measurement of 18-h area under the cortisol concentration–time curve was recommended for determining equivalent systemic exposure. For bronchodilators, methacholine challenge was recommended as the most sensitive method of determining the relative amount of β-agonist or anti-muscarinic agent delivered to the airways. Whilst some agencies, such as the Food and Drug Administration (FDA), do not require measuring systemic effects when pharmacokinetic measurements are feasible, the European Medicines Agency requires measurement of heart rate and serum potassium, and some require serial electrocardiograms when bioequivalence is not established by pharmacokinetic (PK) studies. The Panel Discussion focused on whether PK would be the most sensitive marker of bioequivalence. Furthermore, there was much discussion about the FDA draft guidance for generic fluticasone propionate/salmeterol. The opinion was expressed that the study design is not capable of detecting a non-equivalent product and would require an unfeasibly large sample size. Electronic ISSN: 1550-7416 Topics: Chemistry and Pharmacology Published by Springer on behalf of The American Association of Pharmaceutical Scientists (AAPS). 3 PAPER CURRENT Construction of Lagrangian and Hamiltonian structures starting from one constant of motion (2015) Publication Date: 2015-02-28 Description: Abstract The problem of the construction of Lagrangian and Hamiltonian structures starting from two first-order equations of motion is presented. This approach requires the knowledge of one (time independent) constant of motion for the dynamical system only. The Hamiltonian and Lagrangian structures are constructed, the Hamilton–Jacobi equation is then written and solved, and the second (time dependent) constant of the motion for the problem is explicitly exhibited. Print ISSN: 0001-5970 Electronic ISSN: 1619-6937 Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics Published by Springer 4 PAPER CURRENT A quasi-3D tangential shear deformation theory with four unknowns for functionally graded plates (2015) Publication Date: 2015-02-28 Description: Abstract A so far unavailable quasi-3D trigonometric shear deformation theory for the bending analysis of functionally graded plates is presented. This theory considers the thickness-stretching effect ( $${\varepsilon_{zz } \neq 0}$$ ) by modeling the displacement field with just four unknowns and rich trigonometric shear strain shape functions. The principle of virtual works is used to derive the governing equations and boundary conditions. Results from this theory are compared with the CPT, first-order shear deformation theory (FSDT), and other quasi-3D HSDTs. In conclusion, this theory is more accurate than the CPT and FSDT and behaves as well as quasi-3D HSDTs having much less number of unknowns. Print ISSN: 0001-5970 Electronic ISSN: 1619-6937 Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics Published by Springer 5 PAPER CURRENT Pre-processing of Fourier transform infrared spectra by means of multivariate analysis implemented in the R environment (2015) Publication Date: 2015-02-28 Description: Analyst, 2015, Advance ArticleDOI: 10.1039/C5AN00002E, PaperKrzysztof Banas, Agnieszka Banas, Mariusz Gajda, Bohdan Pawlicki, Wojciech M. Kwiatek, Mark B. H. BreeseSegmentation of the hyperspectral dataset by using hierarchical cluster analysis shows its advantage over the traditional approach based on the average intensity.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Print ISSN: 0003-2654 Electronic ISSN: 1364-5528 Topics: Chemistry and Pharmacology Published by Royal Society of Chemistry (RSC) 6 PAPER CURRENT A novel method for the analysis of clinical biomarkers to investigate the effect of diet on health in a rat model (2015) Publication Date: 2015-02-28 Description: Analyst, 2015, Accepted ManuscriptDOI: 10.1039/C5AN00182J, PaperMichael Cauchi, Kerry-Anne Hopes, Christopher Walton, Hilary MacQueen, WS Wassif, Claire TurnerExperiments into the relationship between diet and health have been an area of high interest for a long time. In this study, we investigate the application of multivariate data analysis...The content of this RSS Feed (c) The Royal Society of Chemistry Print ISSN: 0003-2654 Electronic ISSN: 1364-5528 Topics: Chemistry and Pharmacology Published by Royal Society of Chemistry (RSC) 7 PAPER CURRENT Fast Fluorescence-Based Microfluidic Method for Measuring Minimum Miscibility Pressure of CO2 in Crude Oils (2015) Publication Date: 2015-02-28 Description: Analytical ChemistryDOI: 10.1021/ac5047856 Print ISSN: 0003-2700 Electronic ISSN: 1520-6882 Topics: Chemistry and Pharmacology Published by American Chemical Society (ACS) 8 PAPER CURRENT Algorithms, Vol. 8, Pages 60-81: The Parameterized Complexity of the Rainbow Subgraph Problem (2015) Publication Date: 2015-02-28 Description: The NP-hard RAINBOW SUBGRAPH problem, motivated from bioinformatics, is to find in an edge-colored graph a subgraph that contains each edge color exactly once and has at most $$k$$ vertices. We examine the parameterized complexity of RAINBOW SUBGRAPH for paths, trees, and general graphs. We show that RAINBOW SUBGRAPH  is W[1]-hard with respect to the parameter $$k$$ and also with respect to the dual parameter $$\ell:=n-k$$ where $$n$$ is the number of vertices. Hence, we examine parameter combinations and show, for example, a polynomial-size problem kernel for the combined parameter $$\ell$$ and maximum number of colors incident with any vertex''. Additionally, we show APX-hardness even if the input graph is a properly edge-colored path in which every color occurs at most twice. Electronic ISSN: 1999-4893 Topics: Computer Science Published by MDPI Publishing 9 PAPER CURRENT Evaluation of pulsed electromembrane extraction for the analysis of diclofenac and mefenamic acid in biological fluids (2015) Publication Date: 2015-02-28 Description: Anal. Methods, 2015, Advance ArticleDOI: 10.1039/C4AY02422B, PaperLida Fotouhi, Shahram Seidi, Yadollah Yamini, Elham HosseiniIn the present study, electromembrane extraction (EME) and pulsed electromembrane extraction (PEME) coupled with high-performance liquid chromatography (HPLC) were compared for the extraction of two acidic drugs including diclofenac (DIC) and mefenamic acid (MEF).To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Print ISSN: 1759-9660 Electronic ISSN: 1759-9679 Topics: Chemistry and Pharmacology Published by Royal Society of Chemistry (RSC) 10 PAPER CURRENT Simultaneous Time-Lamination Imaging of Protein Association Using a Split Fluorescent Timer Protein (2015) Publication Date: 2015-02-28 Description: Analytical ChemistryDOI: 10.1021/ac504583t Print ISSN: 0003-2700 Electronic ISSN: 1520-6882 Topics: Chemistry and Pharmacology Published by American Chemical Society (ACS)