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Major Emphasis (major + emphasis)
Selected AbstractsRational Design of Conjugated Polymer Supramolecules with Tunable Colorimetric ResponsesADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Dong June Ahn Abstract Polydiacetylenes (PDAs), a family of highly ,-conjugated polymers, have unique characteristics associated with their ability to self-assemble. Disruption of the extensively delocalized enyne backbones of molecularly ordered PDA sidechains induces a blue-to-red color change, which has been elegantly applied in the design of chemosensors. Recently, colorimetrically reversible PDAs have received significant attention, not only to gain a better understanding of the fundamentals of PDA chromism, but also to develop methodologies to overcome limitations associated with their colorimetrically irreversible counterparts. In this article, recent progress made in the field of colorimetrically tunable (reversible, stable, or sensitive) PDAs is described. Major emphasis is given to rational design strategies developed in our group. Relevant mechanistic investigations, a diagnostic method to test colorimetric reversibility, as well as future challenges in this area will be also discussed. [source] Deficiency of oncoretrovirally transduced hematopoietic stem cells and correction through ex vivo expansionTHE JOURNAL OF GENE MEDICINE, Issue 2 2005David Bryder Abstract Background Extensive efforts to develop hematopoietic stem cell (HSC) based gene therapy have been hampered by low gene marking. Major emphasis has so far been directed at improving gene transfer efficiency, but low gene marking in transplanted recipients might equally well reflect compromised repopulating activity of transduced cells, competing for reconstitution with endogenous and unmanipulated stem cells. Methods The autologous settings of clinical gene therapy protocols preclude evaluation of changes in repopulating ability following transduction; however, using a congenic mouse model, allowing for direct evaluation of gene marking of lympho-myeloid progeny, we show here that these issues can be accurately addressed. Results We demonstrate that conditions supporting in vitro stem cell self-renewal efficiently promote oncoretroviral-mediated gene transfer to multipotent adult bone marrow stem cells, without prior in vivo conditioning. Despite using optimized culture conditions, transduction resulted in striking losses of repopulating activity, translating into low numbers of gene marked cells in competitively repopulated mice. Subjecting transduced HSCs to an ex vivo expansion protocol following the transduction procedure could partially reverse this loss. Conclusions These studies suggest that loss of repopulating ability of transduced HSCs rather than low gene transfer efficiency might be the main problem in clinical gene therapy protocols, and that a clinically feasible ex vivo expansion approach post-transduction can markedly improve reconstitution with gene marked stem cells. Copyright © 2004 John Wiley & Sons, Ltd. [source] Considerations for the Recovery of Recombinant Proteins from PlantsBIOTECHNOLOGY PROGRESS, Issue 4 2004Todd J. Menkhaus The past 5 years have seen the commercialization of two recombinant protein products from transgenic plants, and many recombinant therapeutic proteins produced in plants are currently undergoing development. The emergence of plants as an alternative production host has brought new challenges and opportunities to downstream processing efforts. Plant hosts contain a unique set of matrix contaminants (proteins, oils, phenolic compounds, etc.) that must be removed during purification of the target protein. Furthermore, plant solids, which require early removal after extraction, are generally in higher concentration, wider in size range, and denser than traditional bacterial and mammalian cell culture debris. At the same time, there remains the desire to incorporate highly selective and integrative separation technologies (those capable of performing multiple tasks) during the purification process from plant material. The general plant processing and purification scheme consists of isolation of the plant tissue containing the recombinant protein, fractionation of the tissue along with particle size reduction, extraction of the target protein into an aqueous medium, clarification of the crude extract, and finally purification of the product. Each of these areas will be discussed here, focusing on what has been learned and where potential concerns remain. We also present details of how the choice of plant host, along with location within the plant for targeting the recombinant protein, can play an important role in the ultimate ease of recovery and the emergence of regulations governing plant hosts. Major emphasis is placed on three crops, canola, corn, and soy, with brief discussions of tobacco and rice. [source] THE INITIAL IMPACTS OF A MATCHED SAVINGS PROGRAM: THE SAVER PLUS PROGRAMECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 1 2006ROSLYN RUSSELL A major emphasis in policy focus in recent years has been to promote greater levels of saving and financial inclusion in Australia. A number of studies have identified that low-income households and households with children have lower saving propensities. This paper explores the effectiveness of a particular matched savings program, Saver Plus, in promoting savings amongst low-income families that are typically at the margin of the financial sector. While noting the limitations of the lack of a formal control group, the results appear to suggest that the Saver Plus program, with its involvement of community groups, a financial education component, and co-contribution arrangements may have been successful in encouraging savings behaviour. [source] The ubiquitin-proteasome system and its role in ethanol-induced disordersADDICTION BIOLOGY, Issue 1 2002Terrence M. Donohue Jr The levels of these proteins are controlled by their rates of degradation. Similarly, protein catabolism plays a crucial role in prolonging cellular life by destroying damaged proteins that are potentially cytotoxic. A major player in these catabolic reactions is the ubiquitin-proteasome system, a novel proteolytic system that has become the primary proteolytic pathway in eukaryotic cells. Ubiquitin-mediated proteolysis is now regarded as the major pathway by which most intracellular proteins are destroyed. Equally important, from a toxicological standpoint, is that the ubiquitin-proteasome system is also widely considered to be a cellular defense mechanism, since it is involved in the removal of damaged proteins generated by adduct formation and oxidative stress. This review describes the history and the components of the ubiquitin-proteasome system, its regulation and its role in pathological states, with the major emphasis on ethanol-induced organ injury. The available literature cited here deals mainly with the effects of ethanol consumption on the ubiquitin-proteasome pathway in the liver. However, since this proteolytic system is an essential pathway in all cells it is an attractive experimental model and therapeutic target in extrahepatic organs such as the brain and heart that are also affected by excessive alcohol consumption. [source] The 5th International Symposium on Sturgeons: a conference with major emphasis on conservation, environmental mitigation and sustainable use of the sturgeon resourcesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2006Article first published online: 10 JUL 200 First page of article [source] The 5th International Symposium on Sturgeons: a conference with major emphasis on conservation, environmental mitigation and sustainable use of the sturgeon resourcesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2006Harald Rosenthal First page of article [source] An islet in distress: , cell failure in type 2 diabetesJOURNAL OF DIABETES INVESTIGATION, Issue 4 2010Takeshi Ogihara Abstract Over 200 million people worldwide suffer from diabetes, a disorder of glucose homeostasis. The majority of these individuals are diagnosed with type 2 diabetes. It has traditionally been thought that tissue resistance to the action of insulin is the primary defect in type 2 diabetes. However, recent longitudinal and genome-wide association studies have shown that insulin resistance is more likely to be a precondition, and that the failure of the pancreatic , cell to meet the increased insulin requirements is the triggering factor in the development of type 2 diabetes. A major emphasis in diabetes research has therefore shifted to understanding the causes of , cell failure. Collectively, these studies have implicated a complex network of triggers, which activate intersecting execution pathways leading to , cell dysfunction and death. In the present review, we discuss these triggers (glucotoxicity, lipotoxicity, amyloid and cytokines) with respect to the pathways they activate (oxidative stress, inflammation and endoplasmic reticulum stress) and propose a model for understanding , cell failure in type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00021.x, 2010) [source] Separation of chiral mixtures in real SMB units: The FlexSMB-LSRE®AICHE JOURNAL, Issue 1 2010Pedro Sá Gomes Abstract In this work, a procedure for the separation of a racemic mixture of guaifenesin onto a chiral stationary phase (Chiralpak AD), by means of Simulated Moving Bed (SMB) technology, is presented in four major steps: (1) search for the suitable stationary and mobile phases; (2) determination of sorption parameters and validation by frontal analysis; (3) modeling and design of the SMB unit; and (4) operation and demonstration. A major emphasis is given to the common deviations that "real" SMB units present when compared with the theoretical apparatus (due to tubing and equipment dead volumes, switching time asymmetries and delays, pumps flow rates variations). These deviations are analyzed before and after the design and construction of the FlexSMB-LSRE® unit, a new flexible unit, hereby presented. A detailed model that takes into account tubing and equipment dead volumes, as well as switching time asymmetries and delay, was used to study and compare different dead volumes design and compensating strategies. It is shown that all these approaches can be converged into a switching time compensating strategy. This approach served to predict the experimental operating conditions and run a classical SMB experiment, which afterwards was compared with the simulated profiles obtained for the FlexSMB-LSRE® unit. The result of the separation was guaifenesin enantiomers with purities above 98% and a productivity value of 23 genantiomer/(dm3 CSP day). © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Bivalve Shellfish Quality in the USA: From the Hatchery to the ConsumerJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2010Daniel P. Cheney Shellfish aquaculture has had a long tradition in Asia, Europe, and the western USA, but it is only within the past century that significant cultural and handling practices have been identified, developed, and introduced to improve and enhance shellfish food quality. Shellfish are now being marketed with an emphasis on product quality, product variety, reduced human health risk, and improved ease of preparation. Aquacultured bivalve shellfish products must now have the food quality characteristics of other high-quality seafood products and must meet accepted standards of taste, color, texture, and odor. This review summarizes current efforts within the shellfish industry to improve the food quality of aquacultured bivalve shellfish in the following focus areas: (i) genetic selection and controlled breeding; (ii) production tools; (iii) food safety protection and enhancement; and (iv) processing and creative marketing efforts, with major emphasis on the US shellfish aquaculture sector. [source] | |||||||||||||