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Tremendous Potential (tremendous + potential)
Selected AbstractsAmphiphilic block copolymer micelles for nanoscale drug deliveryDRUG DEVELOPMENT RESEARCH, Issue 1 2006Glen S. Kwon Abstract Amphiphilic block copolymers can assemble into supramolecular core-shell structures, termed ABC micelles, that have proven utility in drug delivery, particularly for drug solubilization. Several examples have entered clinical trials, attesting to the biocompatibility of ABCs and the potential advantages for drug delivery, e.g., low toxicity relative to Cremophor® EL, a surfactant commonly used for drug solubilization. Several examples of ABC micelles demonstrate potential for prolonged circulation in blood. Coupled with novel strategies toward controlled release of drug, nanoscale ABC micelles have tremendous potential for the targeting of antitumor agents, many of which are poorly water soluble and possess dose-limiting toxicity. Drug Dev. Res. 67:15,22, 2006. © 2006 Wiley-Liss, Inc. [source] Cover Picture: Biomineralized Polysaccharide Capsules for Encapsulation, Organization, and Delivery of Human Cell Types and Growth Factors (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 6 2005Mater. Abstract The cover shows biomineralized polysaccharide capsules with specifiable make-up, which can provide microenvironments for stabilization, growth, and differentiation of human cell types, as reported by Oreffo and co-workers on p.,917. The capsules are amenable to complexation with a range of bioactive molecules and cells, offering tremendous potential as multifunctional scaffolds and delivery vehicles in tissue regeneration of hard and soft tissues. The construction of biomimetic microenvironments with specific chemical and physical cues for the organization and modulation of a variety of cell populations is of key importance in tissue engineering. We show that a range of human cell types, including promyoblasts, chondrocytes, adipocytes, adenovirally transduced osteoprogenitors, immunoselected mesenchymal stem cells, and the osteogenic factor, rhBMP-2 (BMP: bone morphogenic protein), can be successfully encapsulated within mineralized polysaccharide capsules without loss of function in vivo. By controlling the extent of mineralization within the alginate/chitosan shell membrane, degradation of the shell wall and release of cells or rhBMP-2 into the surrounding medium can be regulated. In addition, we describe for the first time the ability to generate bead-in-bead capsules consisting of spatially separated cell populations and temporally separated biomolecule release, entrapped within alginate/chitosan shells of variable thickness, mineralization, and stability. Such materials offer significant potential as multifunctional scaffolds and delivery vehicles in tissue regeneration of hard and soft tissues. [source] Isolation and identification of 1,-hydroxy-3-epi-vitamin D3, a potent suppressor of parathyroid hormone secretionJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2005Alex J. Brown Abstract Since our original demonstration of the metabolism of 1,,25(OH)2D3 into 1,,25(OH)2 -3-epi-D3 in human keratinocytes, there have been several reports indicating that epimerization of the 3 hydroxyl group of vitamin D compounds is a common metabolic process. Recent studies reported the metabolism of 25OHD3 and 24(R),25(OH)2D3 into their respective C-3 epimers, indicating that the presence of 1, hydroxyl group is not necessary for the 3-epimerization of vitamin D compounds. To determine whether the presence of a 25 hydroxyl group is required for 3-epimerization of vitamin D compounds, we investigated the metabolism of 1,OHD3, a non-25 hydroxylated vitamin D compound, in rat osteosarcoma cells (ROS 17/2.8). We noted metabolism of 1,OHD3 into a less polar metabolite which was unequivocally identified as 1,OH-3-epi-D3 using the techniques of HPLC, GC/MS, and 1H-NMR analysis. We also identified 1,OH-3-epi-D3 as a circulating metabolite in rats treated with pharmacological concentrations of 1,OHD3. Thus, these results indicated that the presence of a 25 hydroxyl group is not required for 3-epimerization of vitamin D compounds. Furthermore, the results from the same studies also provided evidence to indicate that 1,OH-3-epi-D3, like 1,OHD3, is hydroxylated at C-25. We then evaluated the biological activities of 1,OH-3-epi-D3. Treatment of normal rats every other day for 7 days with 2.5 nmol/kg of 1,OH-3-epi-D3 did not raise serum calcium, while the same dose of 1,OHD3 increased serum calcium by 3.39,±,0.52 mg/dl. Interestingly, in the same rats which received 1,OH-3-epi-D3 we also noted a reduction in circulating PTH levels by 65,±,7%. This ability of 1,OH-3-epi-D3 to suppress PTH levels in normal rats without altering serum calcium was further tested in rats with reduced renal function. The results indicated that the ED50 of 1,OH-3-epi-D3 for suppression of PTH was only slightly higher than that of 1,,25(OH)2D3, but that the threshold dose of the development of hypercalcemia (total serum Ca >,10.5 mg/dl) was nearly 80 times higher. These findings indicate that 1,OH-3-epi-D3 is a highly selective vitamin D analog with tremendous potential for treatment of secondary hyperparathyroidism in chronic renal failure patients. © 2005 Wiley-Liss, Inc. [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] The case for sequencing the genome of the electric eel Electrophorus electricusJOURNAL OF FISH BIOLOGY, Issue 2 2008J. S. Albert A substantial international community of biologists have proposed the electric eel Electrophorus electricus (Teleostei: Gymnotiformes) as an important candidate for genome sequencing. In this study, the authors outline the unique advantages that a genome sequencing project of this species would offer society for developing new ways of producing and storing electricity. Over tens of millions of years, electric fish have evolved an exceptional capacity to generate a weak (millivolt) electric field in the water near their body from specialized muscle-derived electric organs, and simultaneously, to sense changes in this field that occur when it interacts with foreign objects. This electric sense is used both to navigate and orient in murky tropical waters and to communicate with other members of the same species. Some species, such as the electric eel, have also evolved a strong voltage organ as a means of stunning prey. This organism, and a handful of others scattered worldwide, convert chemical energy from food directly into workable electric energy and could provide important clues on how this process could be manipulated for human benefit. Electric fishes have been used as models for the study of basic biological and behavioural mechanisms for more than 40 years by a large and growing research community. These fishes represent a rich source of experimental material in the areas of excitable membranes, neurochemistry, cellular differentiation, spinal cord regeneration, animal behaviour and the evolution of novel sensory and motor organs. Studies on electric fishes also have tremendous potential as a model for the study of developmental or disease processes, such as muscular dystrophy and spinal cord regeneration. Access to the genome sequence of E. electricus will provide society with a whole new set of molecular tools for understanding the biophysical control of electromotive molecules, excitable membranes and the cellular production of weak and strong electric fields. Understanding the regulation of ion channel genes will be central for efforts to induce the differentiation of electrogenic cells in other tissues and organisms and to control the intrinsic electric behaviours of these cells. Dense genomic sequence information of E. electricus will also help elucidate the genetic basis for the origin and adaptive diversification of a novel vertebrate tissue. The value of existing resources within the community of electric fish research will be greatly enhanced across a broad range of physiological and environmental sciences by having a draft genome sequence of the electric eel. [source] Hairy Root and Its Application in Plant Genetic EngineeringJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2006Zhi-Bi Hu Abstract Agrobacterium rhizogenes Conn. causes hairy root disease in plants. Hairy root-infected A. rhizogenes is characterized by a high growth rate and genetic stability. Hairy root cultures have been proven to be an efficient means of producing secondary metabolites that are normally biosynthesized in roots of differentiated plants. Furthermore, a transgenic root system offers tremendous potential for introducing additional genes along with the Ri plasmid, especially with modified genes, into medicinal plant cells with A. rhizogenes vector systems. The cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. Moreover, the cultures can be used to elucidate the intermediates and key enzymes involved in the biosynthesis of secondary metabolites. The present article discusses various applications of hairy root cultures in plant genetic engineering and potential problems associated with them. (Managing editor: Wei Wang) [source] Probing DNA,peptide interaction forces at the single-molecule levelJOURNAL OF PEPTIDE SCIENCE, Issue 12 2006Norbert Sewald Abstract The versatility of chemical peptide synthesis combined with the high sensitivity of AFM single-molecule force spectroscopy allows us to investigate, quantify, and control molecular recognition processes (molecular nanotechnology), offering a tremendous potential in chemical biology. Single-molecule force spectroscopy experiments are able to detect fast intermediate transition states, details of the energy landscape, and structural changes, while avoiding multiple binding events that can occur under ensemble conditions. Dynamic force spectroscopy (DFS) is even able to provide data on the complex lifetime. This minireview outlines the biophysical methodology, discusses different experimental set-ups, and presents representative results in the form of two case studies, both dealing with DNA-binding peptides. They may serve as model systems, e.g., for transcription factors or gene transfection agents. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd. [source] Phase Transformation and Tunable Piezoelectric Properties of Lead-Free (Na0.52K0.48,xLix)(Nb1,x,ySbyTax)O3 SystemJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2009Ruzhong Zuo Lead-free (Na0.52K0.48,x)(Nb1,x,ySby)O3 - xLiTaO3 (NKNS,LT) piezoelectric ceramics have been fabricated by ordinary sintering. A special attention was paid to the composition design through which the dielectric and piezoelectric properties of the (Li, Ta, Sb) modified NKN systems were significantly promoted. A property spectrum was generated with a particular discussion on the relationship between the Sb content, the LT content, the polymorphic phase transition, and the electrical properties and their temperature stability. Excellent and tunable electrical properties of d33=242,400 pC/N, kp=36%,54%, , and Tc=230°,430°C demonstrate a tremendous potential of the compositions studied for device applications. [source] Developing a Service-Learning Curriculum for LinguisticsLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 4 2010Colleen M. Fitzgerald Service-learning integrates community service into a credit-earning course to enrich the learning experience and pair practice with theory in some content area. Linguistics courses offer tremendous potential for service-learning because there are a variety of ways in which language-related theory can be put into practice. This paper outlines the development of a service-learning curriculum for linguistics courses. While examples come from a project where students tutored adult second language learners of English, the activities in this paper extend well to other linguistics courses. Reflection is essential to service-learning, so necessary background and examples of it as a structured learning tool appear here. A second assessment tool, an anonymous online survey taken before and after tutoring, was used to explore any impact on language and diversity attitudes. More generally, service-learning has the potential to positively affect career development, to generate a sense of civic engagement, to facilitate greater understanding of other cultures and races and to make a difference in local communities. [source] Access to large spoken archives: Uses and technology.PROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2002Sponsored by SIG VIS With recent advances in information technology, digital archiving is emerging as an important and practical method for capturing the human experience. Large amounts of spoken materials and audiovisual materials in which speech is an important component are becoming available. This panel will discuss the uses of these mateials for education, information retrieval and dissemination, and research, the requirements that arise from these uses, and speech recognition and retrieval technologies being developed to meet these requirements. These materials have tremendous potential for enriching the presentation of information in education, newscasts and documentaries, but retrieval from and access to these large repositories pose significant challenges. The panel will provide an overview of these issues. [source] Generic plasmid DNA production platform incorporating low metabolic burden seed-stock and fed-batch fermentation processes,BIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009James A. Williams Abstract DNA vaccines have tremendous potential for rapid deployment in pandemic applications, wherein a new antigen is "plugged" into a validated vector, and rapidly produced in a validated, fermentation,purification process. For this application, it is essential that the vector and fermentation process function with a variety of different antigen genes. However, many antigen genes are unpredictably "toxic" or otherwise low yielding in standard fermentation processes. We report cell bank and fermentation process unit operation innovations that reduce plasmid-mediated metabolic burden, enabling successful production of previously known toxic influenza hemagglutinin antigen genes. These processes, combined with vector backbone modifications, doubled fermentation productivity compared to existing high copy vectors, such as pVAX1 and gWiz, resulting in high plasmid yields (up to 2,220 mg/L, 5% of total dry cell weight) even with previously identified toxic or poor producing inserts. Biotechnol. Bioeng. 2009;103: 1129,1143. © 2009 Wiley Periodicals, Inc. [source] Illuminating the host , How RNAi screens shed light on host-pathogen interactionsBIOTECHNOLOGY JOURNAL, Issue 6 2009Miguel Prudêncio Abstract Over millions of years pathogens have coevolved with their respective hosts utilizing host cell functions for survival and replication. Despite remarkable progress in developing antibiotics and vaccination strategies in the last century, infectious diseases still remain a severe threat to human health. Meanwhile, genomic research offers a new era of data-generating platforms that will dramatically enhance our knowledge of pathogens and the diseases they cause. Improvements in gene knockdown studies by RNA interference (RNAi) combined with recent developments in instrumentation and image analysis enable the use of high-throughput screening approaches to elucidate host gene functions exploited by pathogens. Although only a few RNAi-based screens focusing on host genes have been reported so far, these studies have already uncovered hundreds of genes not previously known to be involved in pathogen infection. This review describes recent progress in RNAi screening approaches, highlighting both the limitations and the tremendous potential of RNAi-based screens for the identification of essential host cell factors during infection. [source] Two-photon microscopy of host,pathogen interactions: acquiring a dynamic picture of infection in vivoCELLULAR MICROBIOLOGY, Issue 4 2009Vjollca Konjufca Summary Two-photon (2P) microscopy has become increasingly popular among immunologists for analysing single-cell dynamics in tissues. Researchers are now taking 2P microscopy beyond the study of model antigen systems (e.g. ovalbumin immunization) and are applying the technique to examine infection in vivo. With the appropriate fluorescent probes, 2P imaging can provide high-resolution spatio-temporal information regarding cell behaviour, monitor cell functions and assess various outcomes of infection, such as host cell apoptosis or pathogen proliferation. Imaging of transgenic and knockout mice can be used to probe molecular mechanisms governing the host response to infection. From the microbe side, imaging genetically engineered mutant strains of a pathogen can test the roles of specific virulence factors in pathogenesis. Here, we discuss recent work that has applied 2P microscopy to study models of infection and highlight the tremendous potential that this approach has for investigating host,pathogen interactions. [source] Water Splitting on Semiconductor Catalysts under Visible-Light IrradiationCHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 6 2009Rufino Abstract Splitting image: Sustainable hydrogen production is a key target for the development of alternative, future energy systems that will provide a clean and affordable energy supply. This Minireview focuses on the development of semiconductor catalysts that enable hydrogen production via water splitting upon visible-light irradiation. Sustainable hydrogen production is a key target for the development of alternative, future energy systems that will provide a clean and affordable energy supply. The Sun is a source of silent and precious energy that is distributed fairly all over the Earth daily. However, its tremendous potential as a clean, safe, and economical energy source cannot be exploited unless the energy is accumulated or converted into more useful forms. The conversion of solar energy into hydrogen via the water-splitting process, assisted by photo-semiconductor catalysts, is one of the most promising technologies for the future because large quantities of hydrogen can potentially be generated in a clean and sustainable manner. This Minireview provides an overview of the principles, approaches, and research progress on solar hydrogen production via the water-splitting reaction on photo-semiconductor catalysts. It presents a survey of the advances made over the last decades in the development of catalysts for photochemical water splitting under visible-light irradiation. The Minireview also analyzes the energy requirements and main factors that determine the activity of photocatalysts in the conversion of water into hydrogen and oxygen using sunlight. Remarkable progress has been made since the pioneering work by Fujishima and Honda in 1972, but he development of photocatalysts with improved efficiencies for hydrogen production from water using solar energy still faces major challenges. Research strategies and approaches adopted in the search for active and efficient photocatalysts, for example through new materials and synthesis methods, are presented and analyzed. [source] | |||||||||||||||||||