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Scientific Discussions (scientific + discussion)
Selected AbstractsGas-phase binding of non-covalent protein complexes between bovine pancreatic trypsin inhibitor and its target enzymes studied by electrospray ionization tandem mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2001Victor J. Nesatyy Abstract The potential of electrospray ionization (ESI) mass spectrometry (MS) to detect non-covalent protein complexes has been demonstrated repeteadly. However, questions about correlation of the solution and gas-phase structures of these complexes still produce vigorous scientific discussion. Here, we demonstrate the evaluation of the gas-phase binding of non-covalent protein complexes formed between bovine pancreatic trypsin inhibitor (BPTI) and its target enzymes over a wide range of dissociation constants. Non-covalent protein complexes were detected by ESI-MS. The abundance of the complex ions in the mass spectra is less than expected from the values of the dissociation constants of the complexes in solution. Collisionally activated dissociation (CAD) tandem mass spectrometry (MS/MS) and a collision model for ion activation were used to evaluate the binding of non-covalent complexes in the gas phase. The internal energy required to induce dissociation was calculated for three collision gases (Ne, Ar, Kr) over a wide range of collision gas pressures and energies using an electrospray ionization source. The order of binding energies of the gas-phase ions for non-covalent protein complexes formed by the ESI source and assessed using CAD-MS/MS appears to differ from that of the solution complexes. The implication is that solution structure of these complexes was not preserved in the gas phase. Copyright © 2001 John Wiley & Sons, Ltd. [source] Conference Review: Notes on the "International Congress of Traditional Medicine, Interculturality, and Mental Health," Takiwasi Center, Tarapoto, Peru, June 7,10, 20091ANTHROPOLOGY OF CONSCIOUSNESS, Issue 1 2010BEATRIZ CAIUBY LABATE ABSTRACT English translation by Glenn H. Shepard Jr. Revision by Matthew Meyer This article reports on the recent "International Congress of Traditional Medicine, Interculturality, and Mental Health" held by the Takiwasi Center in Tarapoto in the Peruvian Amazon. The event united 218 researchers and indigenous and religious representatives from 22 countries to present results of scientific discussions and engage in political and ethical debates surrounding the increasingly globalized, transnational, and biomedicalized reach of indigenous medical practices, especially ayahuasca-based therapy and religious practice. The author interviewed several key researchers and representatives present at the event, and presents several important controversies in the field of ayahuasca and traditional medicine. She also reports on the colorful and eclectic nonacademic sessions at the event which included Inca chiropractics, ayahuasca sessions, and various forms of indigenous medicine. The text also reflects on the tragic events that unfolded in nearby Bagua, Peru, on the evening of the meeting, bringing a special urgency to the event's focus on indigenous cultural heritage. [source] Variability and Impact on Design of Bioequivalence StudiesBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 3 2010Achiel Van Peer Revisions of the regulatory guidance are based upon many questions over the past years and sometimes continuing scientific discussions on the use of the most suitable statistical analysis methods and study designs, particularly for drugs and drug products with high within-subject variability. Although high within-subject variability is usually associated with a coefficient of variation of 30% or more, new approaches are available in the literature to allow a gradual increase and a levelling off of the bioequivalence limits to some maximum wider values (e.g. 75,133%), dependent on the increase in the within-subject variability. The two-way, cross-over single dose study measuring parent drug is still the design of first choice. A partial replicate design with repeating the reference product and scaling the bioequivalence for the reference variability are proposed for drugs with high within-subject variability. In case of high variability, more regulatory authorities may accept a two-stage or group-sequential bioequivalence design using appropriately adjusted statistical analysis. This review also considers the mechanisms why drugs and drug products may exhibit large variability. The physiological complexity of the gastrointestinal tract and the interaction with the physicochemical properties of drug substances may contribute to the variation in plasma drug concentration-time profiles of drugs and drug products and to variability between and within subjects. A review of submitted bioequivalence studies at the Food and Drug Administration's Office of Generic Drugs over the period 2003,2005 indicated that extensive pre-systemic metabolism of the drug substance was the most important explanation for consistently high variability drugs, rather than a formulation factor. These scientific efforts are expected to further lead to revisions of earlier regulatory guidance in other regions as is the current situation in Europe. [source] Policy implications of industrial ecology conceptionsBUSINESS STRATEGY AND THE ENVIRONMENT, Issue 5 2004Hilde N. Opoku The way industrial ecology (IE) is conceptualized determines the concept's potential. Different conceptualizations of IE suggest different political solutions and different focuses on the environment. It is not in itself problematic that the debate points in different political directions. The problem occurs when ideologically based argumentation is not made explicit, but instead presented as necessary premises in order to meet IE objectives. An analysis of the implications when two of these conceptions are implemented as strategies for solid waste management illustrates this claim. This author suggests that the contributors to the field make a clear distinction between scientific discussions regarding the analytical framework and policy principles, and discussions regarding practical applications. Only then can the assumption that the concept of industrial ecology has the potential to be a robust and unifying analytical framework and policy principle stand. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment. [source] |