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Selected AbstractsIdentification of rat urinary glycoproteome captured by three lectins using gel and LC-based proteomicsELECTROPHORESIS, Issue 21 2008Pyong-Gon Moon Abstract Many different types of urine proteome studies have been done, but urine glycoprotein studies are insufficient. Therefore, we studied the glycoproteins from rat urine, which could be used to identify biomarkers in an animal model. First, urinary proteins were prepared by using the dialysis and lyophilizing methods from rat urine. Glycoproteins enriched with lectin affinity purification, concanavalin A, jacalin and wheat germ agglutinin from the urinary proteins were separated by means of reverse-phase fast protein LC (FPLC) or 1-D PAGE. Each FPLC fraction and 1-D PAGE gel band were trypsin-digested and analyzed by means of nanoLC-MS/MS. LC-MS/MS analyses were carried out by using linear ion trap MS. A total of 318 rat urinary glycoproteins were identified from the FPLC fractions and gel bands; approximately 90% of identified proteins were confirmed as glycoproteins in Swiss-Prot. Many glycoproteins, known as biomarkers, including C-reactive protein, uromodulin, amyloid beta A4 protein, alpha-1-inhibitor 3, vitamin D-binding protein, kallikrein 3 and fetuin-A were identified in this study. By studying urinary glycoproteins collected from rat, these results may help to assist in identifying urinary biomarkers regarding various types of disease models. [source] Genome-wide P -element screen for Drosophila synaptogenesis mutantsDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2006Faith L.W. Liebl Abstract A molecular understanding of synaptogenesis is a critical step toward the goal of understanding how brains "wire themselves up," and then "rewire" during development and experience. Recent genomic and molecular advances have made it possible to study synaptogenesis on a genomic scale. Here, we describe the results of a screen for genes involved in formation and development of the glutamatergic Drosophila neuromuscular junction (NMJ). We screened 2185 P -element transposon mutants representing insertions in ,16% of the entire Drosophila genome. We first identified recessive lethal mutants, based on the hypothesis that mutations causing severe disruptions in synaptogenesis are likely to be lethal. Two hundred twenty (10%) of all insertions were homozygous lethal. Two hundred five (93%) of these lethal mutants developed at least through late embryogenesis and formed neuromusculature. We examined embryonic/larval NMJs in 202 of these homozygous mutants using immunocytochemistry and confocal microscopy. We identified and classified 88 mutants with altered NMJ morphology. Insertion loci in these mutants encode several different types of proteins, including ATP- and GTPases, cytoskeletal regulators, cell adhesion molecules, kinases, phosphatases, RNA regulators, regulators of protein formation, transcription factors, and transporters. Thirteen percent of insertions are in genes that encode proteins of novel or unknown function. Complementation tests and RT-PCR assays suggest that approximately 51% of the insertion lines carry background mutations. Our results reveal that synaptogenesis requires the coordinated action of many different types of proteins,perhaps as much as 44% of the entire genome,and that transposon mutageneses carry important caveats that must be respected when interpreting results generated using this method. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] Tafoni development in a cryotic environment: an example from Northern Victoria Land, AntarcticaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2008Andrea Strini Abstract Tafoni are a type of cavernous weathering widespread around the world. Despite the extensive distribution of the tafoni, their genesis is not clear and is still a matter of debate, also because they occur in such different climatic conditions and on so many different types of substrate. Geomorphological characterization of more than 60 tafoni in three different Antarctic sites (two coastal and one inland) between 74 and 76° S with sampling of weathering products and salt occurrences are described together with thermal data (on different surfaces) and wind speed recorded in different periods of the year in a selected tafone close to the Italian Antarctic station. The aim of this present study is to provide further information to help understand the processes involved in the growth of tafoni in a cryotic environment, and the relationship of these processes to climate, with particular attention to the thermal regime and the role of wind. The new data presented in this paper suggest that there is no single key factor that drives the tafoni development, although thermal stress seems the most efficient process, particularly if we consider the short-term fluctuations. The data also confirm that other thermal processes, such as freezing,thawing cycles and thermal shock, are not really effective for the development of tafoni in this area. The wind speed measured within the tafoni is half that recorded outside, thus favouring snow accumulation within the tafoni and therefore promoting salt crystallization. On the other hand, the wind effect on the thermal regime within the tafoni seems negligible. While both salt weathering and thermal stress appear active in this cryotic environment, these are azonal processes and are therefore active in other climatic areas where tafoni are widespread (such as the Mediterranean region). Copyright © 2007 John Wiley & Sons, Ltd. [source] Morphology and Growth Process of Carbon Films Prepared by Microwave,/,Radio Frequency Plasma Assisted CVD,ADVANCED ENGINEERING MATERIALS, Issue 7 2008W. Kaczorowski In this work the carbon coatings created by microwave/radio frequency plasma assisted chemical vapour deposition method were investigated. The deposition parameters were optimized in order to obtain homogeneous carbon coatings on such different substrates as AISI 316L steel and silicon. The MW/RF PACVD technique is promising for many different types of applications. [source] Hybrid crossover operators with multiple descendents for real-coded genetic algorithms: Combining neighborhood-based crossover operatorsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2009Ana M. Sánchez Most real-coded genetic algorithm research has focused on developing effective crossover operators, and as a result, many different types of crossover operators have been proposed. Some forms of crossover operators are more suitable to tackle certain problems than others, even at the different stages of the genetic process in the same problem. For this reason, techniques that combine multiple crossovers, called hybrid crossover operators, have been suggested as alternative schemes to the common practice of applying only one crossover model to all the elements in the population. On the other hand, there are operators with multiple offsprings, more than two descendants from two parents, which present a better behavior than the operators with only two descendants, and achieve a good balance between exploration and exploitation. © 2009 Wiley Periodicals, Inc. [source] Ecological feedbacks and the evolution of resistanceJOURNAL OF ANIMAL ECOLOGY, Issue 6 2009Meghan A. Duffy Summary 1. ,The idea that parasites can affect host diversity is pervasive, and the possibility that parasites can increase host diversity is of particular interest. In this review, we focus on diversity in the resistance of hosts to their parasites, and on the different ways in which parasites can increase or decrease this resistance diversity. 2. ,Theoretically, parasites can exert many different types of selection on host populations, which each have consequences for host diversity. Specifically, theory predicts that parasites can exert negative frequency-dependent selection (NFDS) and disruptive selection on resistance, both of which increase host diversity, as well as directional selection and stabilizing selection on resistance, both of which decrease host diversity. 3. ,Despite these theoretical predictions, most biologists think of only NFDS or directional selection for increased resistance in response to parasitism. Here, we present empirical support for all of these types of selection occurring in natural populations. Interestingly, several recent studies demonstrate that there is spatiotemporal variation in the type of selection that occurs (and, therefore, in the effects of parasitism on host diversity). 4. ,A key question that remains, then, is: What determines the type of parasite-mediated selection that occurs? Theory demonstrates that the answer to this question lies, at least in part, with trade-offs associated with resistance. Specifically, the type of evolution that occurs depends critically on the strength and shape of these trade-offs. This, combined with empirical evidence for a strong effect of environment on the shape and strength of trade-offs, may explain the observed spatiotemporal variation in parasite-mediated selection. 5. ,We conclude that spatiotemporal variation in parasite-driven evolution is likely to be common, and that this variation may be driven by ecological factors. We suggest that the feedback between ecological and evolutionary dynamics in host,parasite interactions is likely to be a productive area of research. In particular, studies addressing the role of ecological factors (e.g. productivity and predation regimes) in driving the outcome of parasite-mediated selection on host populations are warranted. Such studies are necessary if we are to understand the mechanisms underlying the observed variation in the effects of parasites on host diversity. [source] Variation in Reproductive Behaviour within a Sex:Neural Systems and Endocrine ActivationJOURNAL OF NEUROENDOCRINOLOGY, Issue 7 2002T. Rhen Abstract Intrasexual variation in reproductive behaviour, morphology and physiology is taxonomically widespread in vertebrates, and is as biologically and ecologically significant as the differences between the sexes. In this review, we examine the diverse patterns of intrasexual variation in reproductive behaviours within vertebrates. By illustrating the genetic, cellular, hormonal and/or neural mechanisms underlying behavioural variation in a number of species, another level of complexity is added to studies of brain organization and function. Such information increases our understanding of the unique and conserved mechanisms underlying sex and individual differences in behaviour in vertebrates as a whole. Here, we show that intrasexual variation in behaviour may be discrete or continuous in nature. Moreover, this variation may be due to polymorphism at a single genetic locus or many loci, or may even be the result of phenotypic plasticity. Phenotypic plasticity simply refers to cases where a single genotype (or individual) can produce (or display) different phenotypes. Defined in this way, plasticity subsumes many different types of behavioural variation. For example, some behavioural phenotypes are established by environmental factors during early ontogeny, others are the result of developmental transitions from one phenotype early in life to another later in life, and still other strategies are facultative with different behaviours displayed in different social contexts. [source] The influence of porosity on the Phillips Cr/silica catalyst 2.JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 3 2009Polyethylene elasticity Abstract The Phillips Cr/silica catalyst produces low levels of long chain branching (LCB) in polyethylene, which have a powerful influence on industrial molding behavior. Although many catalyst and reactor variables determine the degree of LCB, perhaps the most significant of these is the morphology of the silica support. In this study many different types of silicas were converted into Cr/silica catalysts, which were tested in ethylene polymerization, and the resultant polymer elasticity was then determined. In some experiments, the surface area of the catalyst seemed to correlate quite well with polymer elasticity. In other tests, however, no connection with surface area was evident but the pore volume was quite influential. Together, all these studies suggest that it is the degree of structural reinforcement of the silica matrix, rather than any one physical measurement of porosity, that influences elasticity. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 845,865, 2009 [source] Separation techniques for the analysis of artists' acrylic emulsion paintsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 4 2004Dominique Scalarone Abstract Emulsion paints are complex chemical systems. The main problems in their characterization are related to the similarities in polymer composition and to the presence of many different types of additives. Thus high resolution separations, sensitivity, and response specificity are required to identify simultaneously the polymer matrix and the minor components. Especially surfactants and pigments are thought to affect significantly the properties of the paint layers during ageing and their identification is the first step in evaluating the behaviour of these products in working conditions. Representative samples of acrylic emulsion paints for artists have been investigated by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) and size exclusion chromatography-Fourier transform infrared spectroscopy (SEC-FTIR), and the results have been compared. All the analysed samples were bound in ethyl acrylate-methyl methacrylate, poly(EA-co-MMA), or n -butyl acrylate-methyl methacrylate, poly(nBA-co-MMA), copolymers. Two types of nonionic surfactants, ethoxylated fatty alcohols and alkylaryl polyethoxylates, commonly used as emulsifiers and dispersive agents have been identified, together with a number of organic pigments. [source] Inferences from DNA data: population histories, evolutionary processes and forensic match probabilitiesJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 2 2003Ian J. Wilson Summary. We develop a flexible class of Metropolis,Hastings algorithms for drawing inferences about population histories and mutation rates from deoxyribonucleic acid (DNA) sequence data. Match probabilities for use in forensic identification are also obtained, which is particularly useful for mitochondrial DNA profiles. Our data augmentation approach, in which the ancestral DNA data are inferred at each node of the genealogical tree, simplifies likelihood calculations and permits a wide class of mutation models to be employed, so that many different types of DNA sequence data can be analysed within our framework. Moreover, simpler likelihood calculations imply greater freedom for generating tree proposals, so that algorithms with good mixing properties can be implemented. We incorporate the effects of demography by means of simple mechanisms for changes in population size and structure, and we estimate the corresponding demographic parameters, but we do not here allow for the effects of either recombination or selection. We illustrate our methods by application to four human DNA data sets, consisting of DNA sequences, short tandem repeat loci, single-nucleotide polymorphism sites and insertion sites. Two of the data sets are drawn from the male-specific Y-chromosome, one from maternally inherited mitochondrial DNA and one from the , -globin locus on chromosome 11. [source] Medication use and risk of fallsPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 2 2002C. Ineke Neutel PhD, FACE Abstract Purpose Injuries due to falls are an important public health concern, particularly for the elderly, and effective prevention is an ongoing endeavour. The present study has two related objectives: (1) to describe associations between drug use and falls in an institutionalized population, and (2) to identify a high risk subgroup within the larger population. Methods The initial analysis was based on a population of 227 residents who were followed over a 1-year period. Logistic regression techniques were used to estimate odds ratios (ORs) of the association of falls and drug use. The study of potential ,high-risk' groups employed a case,crossover design to estimate the risk of falling associated with starting a new drug course. Results Relatively weak ORs for risk of falling were observed for various drug classes; the highest OR was for benzodiazepines (BZD) at OR=1.8, (unadjusted). Residents taking multiple drugs were at particular risk for falling, e.g. an OR of 6.1, for those using 10+ drugs. The case,crossover analysis indicated that residents starting a new BZD/antipsychotic were at very high risk (OR,=,11.4,) for experiencing a fall. Conclusions Residents who took many different types of medications, as well as residents starting a new BZD/antipsychotics were at greatly increased risk of falling. These are high risk groups where increased monitoring or adjustments to drug regimens could lead to prevention of falls. Copyright © 2002 John Wiley & Sons, Ltd. [source] Commitment to change: Exploring its role in changing physician behavior through continuing educationTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 4 2004Dr. Jacqueline G. Wakefield MD Abstract Statements of commitment to change are advocated both to promote physician change and to assess interventions designed to promote change. Although commitment to change is only one part of a complex process of change, recent progress has established a solid theoretical and research base to support this approach. Studies have demonstrated that it can be used effectively with many different types of educational activities and that statements of "plans to change" practice can predict actual changes. The importance of follow-up as part of the commitment to change model is becoming clearer, although questions remain about the most effective process is accomplishment this and the optimal timing. Further research is needed to establish the effectiveness of the commitment-to-change approach itself, as well as to better understand the functions (and thus the forms) of the different components of the commitment-to-change model. [source] Lentiviral vectors for treating and modeling human CNS disordersTHE JOURNAL OF GENE MEDICINE, Issue 9 2004Mimoun Azzouz Abstract Vectors based on lentiviruses efficiently deliver genes into many different types of primary neurons from a broad range of species including man and the resulting gene expression is long term. These vectors are opening up new approaches for the treatment of neurological diseases such as Parkinson's disease (PD), Huntington's disease (HD), and motor neuron diseases (MNDs). Numerous animal studies have now been undertaken with these vectors and correction of disease models has been obtained. Lentiviral vectors also provide a new strategy for in vivo modeling of human diseases; for example, the lentiviral-mediated overexpression of mutated human ,-synuclein or huntingtin genes in basal ganglia induces neuronal pathology in animals resembling PD and HD in man. These vectors have been refined to a very high level and can be produced safely for the clinic. This review will describe the general features of lentiviral vectors with particular emphasis on vectors derived from the non-primate lentivirus, equine infectious anemia virus (EIAV). It will then describe some key examples of genetic correction and generation of genetic animal models of neurological diseases. The prospects for clinical application of lentiviral vectors for the treatment of PD and MNDs will also be outlined. Copyright © 2004 John Wiley & Sons, Ltd. [source] Perspective: The Stage-Gate® Idea-to-Launch Process,Update, What's New, and NexGen Systems,THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 3 2008Robert G. Cooper Stage-Gate has become a popular system for driving new products to market, and the benefits of using such a robust idea-to-launch system have been well documented. However, there are many misconceptions and challenges in using Stage-Gate. First, Stage-Gate is briefly outlined, noting how the system should work and the structure of both stages and gates. Next, some of the misconceptions about Stage-Gate,it is not a linear process, nor is it a rigid system,are debunked, and explanations of what Stage-Gate is and is not are provided. The challenges faced in employing Stage-Gate are identified, including governance issues, overbureaucratizing the process, and misapplying cost-cutting systems such as Six Sigma and Lean Manufacturing to product innovation. Solutions are offered, including better governance methods such as "gates with teeth," clearly defined gatekeepers, and gatekeeper rules of engagement, as well as ways to deal with bureaucracy, including leaner gates. Next-generation versions of Stage-Gate are introduced, notably a scalable system (to handle many different types and sizes of projects), as well as even more flexible and adaptable versions of Stage-Gate achieved via spiral development and simultaneous execution. Additionally, Stage-Gate now incorporates better decision-making practices including scorecards, success criteria, self-managed gates, electronic and virtual gates, and integration with portfolio management. Improved accountability and continuous improvement are now built into Stage-Gate via a rigorous postlaunch review. Finally, progressive companies are reinventing Stage-Gate for use with "open innovation," whereas others are applying the principles of value stream analysis to yield a leaner version of Stage-Gate. [source] Acute Stroke Care at Rural Hospitals in Idaho: Challenges in Expediting Stroke CareTHE JOURNAL OF RURAL HEALTH, Issue 1 2006James G. Gebhardt MD ABSTRACT:,Context: Thrombolytics are currently the most effective treatment for stroke. However, the National Institute for Neurological Disorders and Stroke criteria for initiation of thrombolytic therapy, most notably the 3-hour time limit from symptom onset, have proven challenging for many rural hospitals to achieve. Purpose: To provide a snapshot of stroke care at rural hospitals in Idaho and to investigate the experiences of these hospitals in expediting stroke care. Methods: Using a standard questionnaire, a telephone survey of hospital staff at 21 rural hospitals in Idaho was performed. The survey focused on acute stroke care practices and strategies to expedite stroke care. Findings: The median number of stroke patients treated per year was 23.3. Patient delays were reported by 77.8% of hospitals, transport delays by 66.7%, in-hospital delays by 61.1%, equipment delays by 22.2%, and ancillary services delays by 61.1%. Approximately 67% of hospitals had implemented a clinical pathway for stroke and 80.0% had provided staff with stroke-specific training. No hospitals surveyed had a designated stroke team, and only 33.3% reported engaging in quality improvement efforts to expedite stroke care. Thrombolytics (tPA) were available and indicated for stroke at 55.6% of the hospitals surveyed. Conclusions: Rural hospitals in Idaho face many difficult challenges as they endeavor to meet the 3-hour deadline for thrombolytic therapy, including limited resources and experience in acute stroke care, and many different types of prehospital and in-hospital delays. [source] Antigenic as Well as Nonantigenic Stimuli Induce Similar Middle Ear Responses in the Rat,THE LARYNGOSCOPE, Issue 2 2003Edith L. G. M. Tonnaer MSc Abstract Objectives/Hypothesis The observation that during otitis media many different types of micro-organisms have been cultured from effusions indicate that, once present in the middle ear cavity, most types of micro-organisms are able to trigger an inflammatory reaction leading to otitis media. The present study was designed to determine the middle ear response after injection of different substances into the middle ear cavity. Study Design To determine whether and to what extent an inflammatory response of the middle ear depends on the entering agent, the response in the tympanic cavity was studied by otomicroscopy and histological examination after inoculation of various substances. Methods Lewis rats were inoculated in transtympanic fashion either with live or heat-killed bacteria (pathogenic and nonpathogenic), Keyhole limpet hemocyanin, active charcoal, or saline. The mucosal response of the challenged middle ears was studied histologically. Results Irrespective of the inoculated substance, no essential differences in the mucosal response were found. The intensity of the inflammatory response was greater when live bacteria were inoculated. Conclusions The present study demonstrates that any substance reaching the middle ear cavity is likely to induce otitis media. These observations emphasize the role of the eustachian tube as "porte d'entrée" in the pathogenesis of this disorder. Determination of specific aspects of the eustachian tube involved in protection or in facilitating bacterial translocation will be important for the understanding of the pathogenesis of otitis media and the subsequent development of new therapeutic strategies. In addition, elucidation of bacterial factors involved in the process of colonization and translocation will be of equal importance. [source] Non-redundant inhibitor of differentiation (Id) gene expression and function in human prostate epithelial cellsTHE PROSTATE, Issue 9 2006Ananthi J. Asirvatham Abstract BACKGROUND The four Id (inhibitor of differentiation) proteins (Id1, Id2, Id3, and Id4) dimerize and neutralize the transcriptional activity of basic helix-loop-helix (bHLH) proteins. The Id proteins negatively regulate differentiation and promote proliferation hence the expression of specific subsets of Id proteins is high in many different types of cancers. However, the expression of all the Id isoforms and their potential function in specific cancer cell types is not known. In this study, the expression and function of all four Id isoforms in prostate cancer cell lines was investigated to gain a better understanding of the role of each Id isoform in normal prostate epithelial and prostate cancer cells. METHODS Id gene and protein expression was evaluated in the context of androgen response. The cellular function of Id isoforms was evaluated by targeted loss of function of Id genes. RESULTS The four Id isoforms are differentially expressed and regulated in normal human prostate epithelial cells versus prostate cancer cell lines DU145 and LNCaP. Id4 is present only in AR positive cells (normal and LNCaP) and its expression regulated by androgens. Loss of Id1 and Id3 expression by siRNA results in loss of proliferation. Loss of Id2 had no effect on proliferation but increased apoptosis. CONCLUSIONS A complex equilibrium between Id isoforms determines the cell fate. Id1 and Id3 target cellular proliferation, Id2 targets apoptosis, and Id4 may act as a potential tumor suppressor in prostate epithelial cells. Prostate 66: 921,935, 2006. © 2006 Wiley-Liss, Inc. [source] The role of Gab family scaffolding adapter proteins in the signal transduction of cytokine and growth factor receptorsCANCER SCIENCE, Issue 12 2003Keigo Nishida The Grb2-associated binder (Gab) family adapter proteins are scaffolding adapter molecules that display sequence similarity with Drosophila DOS (daughter of sevenless), which is a substrate for the protein tyrosine phosphatase Corkscrew. Gab proteins contain a pleckstrin homology (PH) domain and binding sites for SH2 and SH3 domains. A number of studies in multiple systems have implicated Gab in signaling via many different types of receptors, such as growth factor, cytokine, and antigen receptors, and via oncoproteins. Recent studies of Gab1 and Gab2 knockout mice have clearly indicated an important role for Gabs in vivo. Gab1-deficient mice die as embryos with multiple defects in placental, heart, skin, and muscle development. Gab2-deficient mice are viable, but have a defect in the mast cell lineages and in allergic reactions. Given the apparently central role played by Gab signaling via many receptors, delineating the precise mechanism(s) of Gab-mediated signaling is critical to understanding how cytokines, growth factors, and oncoproteins mediate a variety of biological activities: cell growth, differentiation, survival and malignant transformation. [source] THE EFFECT OF NETWORK STRUCTURE ON DYNAMIC TEAM FORMATION IN MULTI-AGENT SYSTEMSCOMPUTATIONAL INTELLIGENCE, Issue 2 2008Matthew E. Gaston Previous studies of team formation in multi-agent systems have typically assumed that the agent social network underlying the agent organization is either not explicitly described or the social network is assumed to take on some regular structure such as a fully connected network or a hierarchy. However, recent studies have shown that real-world networks have a rich and purposeful structure, with common properties being observed in many different types of networks. As multi-agent systems continue to grow in size and complexity, the network structure of such systems will become increasing important for designing efficient, effective agent communities. We present a simple agent-based computational model of team formation, and analyze the theoretical performance of team formation in two simple classes of networks (ring and star topologies). We then give empirical results for team formation in more complex networks under a variety of conditions. From these experiments, we conclude that a key factor in effective team formation is the underlying agent interaction topology that determines the direct interconnections among agents. Specifically, we identify the property of diversity support as a key factor in the effectiveness of network structures for team formation. Scale-free networks, which were developed as a way to model real-world networks, exhibit short average path lengths and hub-like structures. We show that these properties, in turn, result in higher diversity support; as a result, scale-free networks yield higher organizational efficiency than the other classes of networks we have studied. [source] | ||||||||||||||||||||||