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Enhanced Interaction (enhanced + interaction)
Selected AbstractsR120G ,B-crystallin promotes the unfolding of reduced ,-lactalbumin and is inherently unstableFEBS JOURNAL, Issue 3 2005Teresa M. Treweek ,-Crystallin is the principal lens protein which, in addition to its structural role, also acts as a molecular chaperone, to prevent aggregation and precipitation of other lens proteins. One of its two subunits, ,B-crystallin, is also expressed in many nonlenticular tissues, and a natural missense mutation, R120G, has been associated with cataract and desmin-related myopathy, a disorder of skeletal muscles [Vicart P, Caron A, Guicheney P, Li Z, Prevost MC, Faure A, Chateau D, Chapon F, Tome F, Dupret JM, Paulin D & Fardeau M (1998) Nat Genet20, 92,95]. In the present study, real-time 1H-NMR spectroscopy showed that the ability of R120G ,B-crystallin to stabilize the partially folded, molten globule state of ,-lactalbumin was significantly reduced in comparison with wild-type ,B-crystallin. The mutant showed enhanced interaction with, and promoted unfolding of, reduced ,-lactalbumin, but showed limited chaperone activity for other target proteins. Using NMR spectroscopy, gel electrophoresis, and MS, we observed that, unlike the wild-type protein, R120G ,B-crystallin is intrinsically unstable in solution, with unfolding of the protein over time leading to aggregation and progressive truncation from the C-terminus. Light scattering, MS, and size-exclusion chromatography data indicated that R120G ,B-crystallin exists as a larger oligomer than wild-type ,B-crystallin, and its size increases with time. It is likely that removal of the positive charge from R120 of ,B-crystallin causes partial unfolding, increased exposure of hydrophobic regions, and enhances its susceptibility to proteolysis, thus reducing its solubility and promoting its aggregation and complexation with other proteins. These characteristics may explain the involvement of R120G ,B-crystallin with human disease states. [source] Ehealth: Market Potential and Business StrategiesJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 4 2001Pamela Whitten Due to the economic and social priorities afforded health services in the United States, research on new delivery modalities such as the Internet is gaining in popularity. Claims of the Internet's potential range from a promise to revolutionize the fundamental way health care is delivered to a tool for empowering patients through enhanced interaction with providers (Rice, 2001). Even though a great amount of attention has been given to e-health activity, the preponderance of publications to date has focused on the Internet as a source of health information. However important this form of e-health is, this type of service simply does not face the same constraints that must be addressed by those actually delivering health care services or tightly regulated pharmaceutical products. In this paper, we examine e-health by focusing explicitly on the delivery of health care products and services. Our examination of e-health activity is guided by two broad research questions. First, we ask what the potential is for the development of online health care services by examining its potential in major health care service and product sectors. Second, based upon case studies of two online health service firms, we seek to understand the emerging strategies of firms that are attempting to enter the health care market with an entirely online approach. Our examination of current e-health trends, as well as our two case studies, demonstrates the tremendous potential for health-related commercial activity on the Internet. However, our examination of the barriers facing ehealth from the US health system also pointed out the almost insurmountable challenges. We therefore conclude that a "click and mortar" model may perhaps be the optimal strategy for e-health. [source] Early communication of drug safety concerns: a feasibility study on enhancing interaction between the pharmaceutical industry and regulatorsPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 3 2010Elizabeth Swain BPharm, MRPharmS Abstract Purpose The responsibility for monitoring the safety of marketed medicines is shared between regulatory authorities and the pharmaceutical industry and is underpinned by legal obligations on both sides. Both marketing authorisation holders (MAHs) and regulators initially evaluate and investigate potential safety concerns, and then work together on further review as appropriate. We wanted to test the feasibility of enhanced interaction between MAH and regulator via a regular monthly, two-way communication of potential safety concerns between the MAHs and the Medicines and Healthcare Products Regulatory Agency (MHRA). It was envisaged that such a process would aid prioritisation and planning by both parties, avoid duplication of effort and support a collaborative approach for decision making. Methods Four MAHs took part in the pilot, which was conducted between July 2007 and June 2008. Potential safety concerns were exchanged on a monthly basis. The MAH/MHRA proposed a timeline for evaluation of each potential safety concern. The pilot did not include serious public health issues which are immediately reported to regulatory authorities. Results During the pilot, 136 potential safety concerns were exchanged. Thirteen per cent of these resulted in a change to product information for health professionals and patients. There was concurrence between the MAHs and MHRA on timelines proposed for evaluation. Conclusions The pilot proved feasible for the companies involved and indicated potential benefits of a system for avoiding duplication of effort and supporting a collaborative approach to planning and prioritisation of investigation of potential safety concerns between pharmaceutical industry and regulatory authorities. Copyright © 2009 John Wiley & Sons, Ltd. This article was published online on December 27, 2009. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected (08/01/10). [source] How resonance assists hydrogen bonding interactions: An energy decomposition analysisJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2007John Frederick Beck Abstract Block-localized wave function (BLW) method, which is a variant of the ab initio valence bond (VB) theory, was employed to explore the nature of resonance-assisted hydrogen bonds (RAHBs) and to investigate the mechanism of synergistic interplay between , delocalization and hydrogen-bonding interactions. We examined the dimers of formic acid, formamide, 4-pyrimidinone, 2-pyridinone, 2-hydroxpyridine, and 2-hydroxycyclopenta-2,4-dien-1-one. In addition, we studied the interactions in ,-diketone enols with a simplified model, namely the hydrogen bonds of 3-hydroxypropenal with both ethenol and formaldehyde. The intermolecular interaction energies, either with or without the involvement of , resonance, were decomposed into the Hitler-London energy (,EHL), polarization energy (,Epol), charge transfer energy (,ECT), and electron correlation energy (,Ecor) terms. This allows for the examination of the character of hydrogen bonds and the impact of , conjugation on hydrogen bonding interactions. Although it has been proposed that resonance-assisted hydrogen bonds are accompanied with an increasing of covalency character, our analyses showed that the enhanced interactions mostly originate from the classical dipole,dipole (i.e., electrostatic) attraction, as resonance redistributes the electron density and increases the dipole moments in monomers. The covalency of hydrogen bonds, however, changes very little. This disputes the belief that RAHB is primarily covalent in nature. Accordingly, we recommend the term "resonance-assisted binding (RAB)" instead of "resonance-assisted hydrogen bonding (RHAB)" to highlight the electrostatic, which is a long-range effect, rather than the electron transfer nature of the enhanced stabilization in RAHBs. © 2006 Wiley Periodicals, Inc. J Comput Chem 28: 455,466, 2007 [source] On the Interrelationship of Transreactions with Thermal Properties and Dynamic Mechanical Analysis of PTT/PEN BlendsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 16 2009Seyed-Hassan Jafari Abstract An attempt was made to explore the effects of interchange reactions on the crystallization, melting, and dynamic mechanical behavior of binary blends based on poly(trimethylene terephthalate) (PTT)/poly(ethylene 2,6-naphthalate) (PEN). 1H NMR spectroscopy is used to verify the occurrence of interchange reactions at the interface, which are increased upon an increase in the melt processing time and temperature. The crystallinity of PTT was reduced while that of PEN was increased on blending. In addition, the crystallization temperatures of both phases showed depression. A single composition-dependent glass transition temperature (Tg) was detected in the second and subsequent heating thermograms of the blends, which is indicative of miscibility. The cold crystallization of the PTT phase was observed to increase while that of PEN was suppressed on blending. Each phase crystallized individually and a melting point depression was evident, which suggests a certain level of miscibility. Dynamic mechanical thermal analysis corroborated differential scanning calorimetry results. A constructive synergism was observed in the glassy state storage moduli of the blends, which is suggestive of a reduced specific volume of the system because of enhanced interactions and crystallinity. [source] Scaling characteristics and growth of corrosion product films in turbulent flow solution containing saturated CO2MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 1 2009Z. F. Yin Abstract In the present study, the surface and cross-section microstructures of the corrosion films were investigated by SEM and the corrosion rate was measured by mass loss at the various conditions associated with the main influencing factors such as temperature, CO2 partial pressure, and flow velocity. The results indicated that the three factors have obvious characteristics and the enhanced interactions among the main influencing factors intensively influence the formation and growth of corrosion film. In addition, there were two corrosion mechanisms connected with the forming film and damaging film. A new lattice model was proposed to describe the general aspects concerning the formation of the corrosion film at the metal surface/solution interfaces. [source] | |||||||||||||