Home About us Contact
|
Home About us Contact | ||
|
|
||
Effective System (effective + system)
Selected AbstractsGene transfer into chicken embryos as an effective system of analysis in developmental biologyDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2000Sadao Yasugi Chicken embryos have been used as a model animal in developmental biology since the time of comparative and experimental embryology. Recent application of gene transfer techniques to the chicken embryo increases their value as an experimental animal. Today, gene transfer into chicken cells is performed by three major systems, lipofection, electroporation and the virus-mediated method. Each system has its own features and applicability. In this overview and the associated four minireviews, the methods and application of each system will be presented. [source] The pallial basal ganglia pathway modulates the behaviorally driven gene expression of the motor pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Lubica Kubikova Abstract The discrete neural network for songbird vocal communication provides an effective system to study neural mechanisms of learned motor behaviors in vertebrates. This system consists of two pathways , a vocal motor pathway used to produce learned vocalizations and a vocal pallial basal ganglia loop used to learn and modify the vocalizations. However, it is not clear how the loop exerts control over the motor pathway. To study the mechanism, we used expression of the neural activity-induced gene ZENK (or egr-1), which shows singing-regulated expression in a social context-dependent manner: high levels in both pathways when singing undirected and low levels in the lateral part of the loop and in the robust nucleus of the arcopallium (RA) of the motor pathway when singing directed to another animal. Here, we show that there are two parallel interactive parts within the pallial basal ganglia loop, lateral and medial, which modulate singing-driven ZENK expression of the motor pathway nuclei RA and HVC, respectively. Within the loop, the striatal and pallial nuclei appear to have opposing roles; the striatal vocal nucleus lateral AreaX is required for high ZENK expression in its downstream nuclei, particularly during undirected singing, while the pallial vocal lateral magnocellular nucleus of the anterior nidopallium is required for lower expression, particularly during directed singing. These results suggest a dynamic molecular interaction between the basal ganglia pathway and the motor pathway during production of a learned motor behavior. [source] Ki-1/57 interacts with PRMT1 and is a substrate for arginine methylationFEBS JOURNAL, Issue 17 2006Dario O. Passos The human 57 kDa Ki-1 antigen (Ki-1/57) is a cytoplasmic and nuclear protein, associated with Ser/Thr protein kinase activity, and phosphorylated at the serine and threonine residues upon cellular activation. We have shown that Ki-1/57 interacts with chromo-helicase DNA-binding domain protein 3 and with the adaptor/signaling protein receptor of activated kinase 1 in the nucleus. Among the identified proteins that interacted with Ki-1/57 in a yeast two-hybrid system was the protein arginine-methyltransferase-1 (PRMT1). Most interestingly, when PRMT1 was used as bait in a yeast two-hybrid system we were able to identify Ki-1/57 as prey among 14 other interacting proteins, the majority of which are involved in RNA metabolism or in the regulation of transcription. We found that Ki-1/57 and its putative paralog CGI-55 have two conserved Gly/Arg-rich motif clusters (RGG/RXR box, where X is any amino acid) that may be substrates for arginine-methylation by PRMT1. We observed that all Ki-1/57 protein fragments containing RGG/RXR box clusters interact with PRMT1 and are targets for methylation in vitro. Furthermore, we found that Ki-1/57 is a target for methylation in vivo. Using immunofluorescence experiments we observed that treatment of HeLa cells with an inhibitor of methylation, adenosine-2,,3,-dialdehyde (Adox), led to a reduction in the cytoplasmic immunostaining of Ki-1/57, whereas its paralog CGI-55 was partially redistributed from the nucleus to the cytoplasm upon Adox treatment. In summary, our data show that the yeast two-hybrid assay is an effective system for identifying novel PRMT arginine-methylation substrates and may be successfully applied to other members of the growing family of PRMTs. [source] Incorporating structural characteristics for identification of protein methylation sitesJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 9 2009Dray-Ming Shien Abstract Studies over the last few years have identified protein methylation on histones and other proteins that are involved in the regulation of gene transcription. Several works have developed approaches to identify computationally the potential methylation sites on lysine and arginine. Studies of protein tertiary structure have demonstrated that the sites of protein methylation are preferentially in regions that are easily accessible. However, previous studies have not taken into account the solvent-accessible surface area (ASA) that surrounds the methylation sites. This work presents a method named MASA that combines the support vector machine with the sequence and structural characteristics of proteins to identify methylation sites on lysine, arginine, glutamate, and asparagine. Since most experimental methylation sites are not associated with corresponding protein tertiary structures in the Protein Data Bank, the effective solvent-accessible prediction tools have been adopted to determine the potential ASA values of amino acids in proteins. Evaluation of predictive performance by cross-validation indicates that the ASA values around the methylation sites can improve the accuracy of prediction. Additionally, an independent test reveals that the prediction accuracies for methylated lysine and arginine are 80.8 and 85.0%, respectively. Finally, the proposed method is implemented as an effective system for identifying protein methylation sites. The developed web server is freely available at http://MASA.mbc.nctu.edu.tw/. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Oral health care status of homebound elderly in JapanJOURNAL OF ORAL REHABILITATION, Issue 8 2001Masayuki Morishita We examined the present conditions of oral health care in order to contribute towards an effective system to provide oral health care for homebound elderly in Japan. A questionnaire was mailed to homebound elderly subjects (n=908) and returned by mail. A 73·6% response was achieved. The questionnaire was designed to elicit information with respect to the general condition of the subjects and independence of oral health care. About 70% of the subjects were chair- or bed-bound. Among all subjects, 37·6% required partial or full assistance on toothbrushing, 55·6% on cleaning dentures and 46·7% on eating. The degree of oral health care tended to be poor for chair- or bed-bound elderly compared with independent or house-bound elderly. Homebound elderly with lower Activities of Daily Living Scale (ADL) required more support for oral health care compared with elderly with higher ADL. [source] Copolymerization of ethylene with 1-hexene over metallocene catalyst supported on complex of magnesium chloride with tetrahydrofuranJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2004Krystyna Czaja Abstract The study of ethylene/1-hexene copolymerization with the zirconocene catalyst, bis(cyclopentadienyl)zirconium dichloride (Cp2ZrCl2)/methylaluminoxane (MAO), anchored on a MgCl2(THF)2 support was carried out. The influence of 1-hexene concentration in the feed on catalyst productivity and comonomer reactivity as well as other properties was investigated. Additionally, the effect of support modification by the organoaluminum compounds [(MAO, trimethlaluminum (AlMe3), or diethylaluminum chloride (Et2AlCl)] on the behavior of the MgCl2(THF)2/Cp2ZrCl2/MAO catalyst in the copolymerization process and on the properties of the copolymers was explored. Immobilization of the Cp2ZrCl2 compound on the complex magnesium support MgCl2(THF)2 resulted in an effective system for the copolymerization of ethylene with 1-hexene. The modification of the support as well as the kind of organoaluminum compound used as a modifier influenced the activity of the examined catalyst system. Additionally, the profitable influence of immobilization of the homogeneous catalyst as well as modification of the support applied on the molecular weight and molecular weight distribution of the copolymers was established. Finally, with the successive self-nucleation/annealing procedure, the copolymers obtained over both homogeneous and heterogeneous metallocene catalysts were heterogeneous with respect to their chemical composition. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2512,2519, 2004 [source] A highly informative, multiplexed assay for the indirect detection of hemophilia A using five-linked microsatellitesJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 3 2006J. R. HARRAWAY Summary.,Background:,Hemophilia A is a severe bleeding disorder caused by almost 1000 different known mutations in the F8C gene. Direct mutation analysis is sometimes difficult for this disorder. When a mutation cannot be found, linkage analysis can be used for prenatal and carrier diagnosis. Aim:,To develop a rapid and effective system for carrier detection and prenatal diagnosis of hemophilia A based on a single-multiplexed polymerase chain reaction (PCR) reaction utilizing five microsatellite markers. Patients and methods:,Two intronic microsatellites and three other markers flanking the factor VIII gene were ascertained, and primers were designed for multiplex PCR amplification. A kindred with Hemophilia A was tested for linkage using the panel of primers, and informativity in the general population was ascertained by testing 50 unrelated females. Results:,Co-amplification of all microsatellites was optimized using DNA extracted by standard methods. Rapid detection and sizing of products were carried out using an automated DNA sequencer. The combined microsatellite panel was informative in each of the kindreds tested, and in 100% of the 50 unrelated females (95% CI 94.2,100%). Conclusions:,This method enables the indirect detection of hemophilia A for patients in whom mutations cannot be found, facilitating carrier testing and prenatal analysis. It is rapid and straightforward compared with many other published protocols, and offers a high degree of informativity. [source] Chitosan-Hydroxybenzotriazole Aqueous Solution: A Novel Water-Based System for Chitosan FunctionalizationMACROMOLECULAR RAPID COMMUNICATIONS, Issue 13 2006Juthathip Fangkangwanwong Abstract Summary: A chitosan-hydroxybenzotriazole (HOBt) aqueous solution prepared by simply mixing chitosan and HOBt in water provides an effective system to functionalize chitosan in an aqueous environment. This aqueous solution in combination with water-soluble carbodiimide (WSC) allows the conjugation of functional groups onto chitosan under mild conditions without requiring any organic solvents or acid and heat. In this contribution, a series of model reactions that use a novel water-based system of chitosan to functionalize the polymer with boc- L -phenylalanine, poly(ethylene glycol) methyl ether, and dicarboxylated poly(ethylene glycol) is demonstrated. Chitosan-HOBt is effectively conjugated with R-COOH via a water-soluble carbodiimide (WSC) conjugating agent. [source] Adult survivors of children's cancer and their offspringPEDIATRICS INTERNATIONAL, Issue 2 2000Fumio Bessho AbstractBackground: Although it is anticipated in Japan that the number of long-term survivors of children's cancer will rapidly increase and that they will have children, reports of studies concerning the offspring of such survivors have come mainly from western countries. For this reason, it seems that the results of this study will be important. Methods: Ninety-seven survivors of children's cancer, who were diagnosed between 1962 and 1989 and are now older than 20 years old, and their offspring were studied. Results: Of 97 survivors, 30 have married and 23 survivors or their spouses had been pregnant (33 total pregnancies). Twenty-five babies were born and seven pregnancies ended in spontaneous abortion. The abortion rate was not different from that of the Japanese general population. The birthweights of babies born to survivors tended to be lower than those of control subjects. The proportion of babies with birthweights under 2500 g was significantly greater for babies born to survivors than to the control subjects. None of the 25 babies born had congenital anomalies. Subsequent development of these children has been uneventful with no malignancies after a median follow-up period of 4 years 10 months (range: 10 months to 16 years, 3 months). Conclusions: The reproductive activity of children's cancer survivors and the health status of their offspring seem to be satisfactory. However, the sample size of the present study is too small to draw any definite conclusions. Because it is anticipated that the number of long-term survivors of children's cancer will rapidly increase in Japan, it is important to establish an effective system of following up these survivors and their offspring in order to provide them with appropriate suggestions for a better quality of life. [source] An effective system for detecting Iris yellow spot virus transmission by Thrips tabaciPLANT PATHOLOGY, Issue 3 2010T. Inoue A simple, effective and convenient laboratory leaf system was developed to detect transmission of Iris yellow spot virus (IYSV) by thrips. It was shown that IYSV was transmitted highly efficiently by adults and also by larvae of five thelytokous populations of Thripstabaci from distinct areas in Japan: over all these populations, transmission efficiency of adults ranged from 20·4% (19/93) to 41·1% (76/185) and that of larvae from 17·3% (14/81) to 44·1% (67/152). Finally, it was demonstrated that IYSV infection was not detrimental to the development and fecundity of thrips until early adulthood. Larval mortalities of virus-exposed thrips were higher than in their unexposed counterparts in all three populations, but the differences were not significant. The results demonstrated that T. tabaci populations have considerable potential to cause outbreaks of IYSV and spread the disease because of their efficient transmission of the virus. [source] One-pot synthesis in aqueous system for water-soluble chitosan- graft -poly(ethylene glycol) methyl etherBIOPOLYMERS, Issue 6 2006J. Fangkangwanwong Abstract Chitosan is functionalized with poly(ethylene glycol) methyl ether (mPEG) at the amino and hydroxyl groups via a single step reaction in a homogeneous aqueous system. A chitosan aqueous solution obtained from the mixture of chitosan and hydroxybenzotriazole (HOBt) in water is a key factor in providing mild conditions to conjugate mPEG by using a carbodiimide conjugating agent. The reaction at ambient temperature for 24 h gives chitosan- g -mPEG with water solubility with mPEG content as high as 42%. This work demonstrates that a water-soluble chitosan,HOBt complex is an effective system for the preparation of chitosan derivatives via the aqueous system without the use of acids or organic solvents. © 2006 Wiley Periodicals, Inc. Biopolymers 82:580,586, 2006 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] An architecture for exploiting multi-core processors to parallelize network intrusion preventionCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2009Robin Sommer Abstract It is becoming increasingly difficult to implement effective systems for preventing network attacks, due to the combination of the rising sophistication of attacks requiring more complex analyses to detect; the relentless growth in the volume of network traffic that we must analyze; and, critically, the failure in recent years for uniprocessor performance to sustain the exponential gains that for so many years CPUs have enjoyed. For commodity hardware, tomorrow's performance gains will instead come from multi-core architectures in which a whole set of CPUs executes concurrently. Taking advantage of the full power of multi-core processors for network intrusion prevention requires an in-depth approach. In this work we frame an architecture customized for parallel execution of network attack analysis. At the lowest layer of the architecture is an ,Active Network Interface', a custom device based on an inexpensive FPGA platform. The analysis itself is structured as an event-based system, which allows us to find many opportunities for concurrent execution, since events introduce a natural asynchrony into the analysis while still maintaining good cache locality. A preliminary evaluation demonstrates the potential of this architecture. Copyright © 2009 John Wiley & Sons, Ltd. [source] What Happens to the State in Conflict?: Political Analysis as a Tool for Planning Humanitarian AssistanceDISASTERS, Issue 4 2000Lionel Cliffe It is now part of received wisdom that humanitarian assistance in conflict and post-conflict situations may be ineffective or even counterproductive in the absence of an informed understanding of the broader political context in which so-called ,complex political emergencies' (CPEs) occur. Though recognising that specific cases have to be understood in their own terms, this article offers a framework for incorporating political analysis in policy design. It is based on a programme of research on a number of countries in Africa and Asia over the last four years. It argues that the starting-point should be an analysis of crises of authority within contemporary nation-states which convert conflict (a feature of all political systems) into violent conflict; of how such conflict may in turn generate more problems for, or even destroy, the state; of the deep-rooted political, institutional and developmental legacies of political violence; and of the difficulties that complicate the restoration of legitimate and effective systems of governance after the ,termination' of conflict. It then lists a series of questions which such an analysis would need to ask , less in order to provide a comprehensive check-list than to uncover underlying political processes and links. It is hoped these may be used not only to understand the political dynamics of emergencies, but also to identify what kinds of policy action should and should not be given priority by practitioners. [source] From policy lessons to policy actions: motivation to take evaluation seriouslyPUBLIC ADMINISTRATION & DEVELOPMENT, Issue 4 2004Gustavo Gordillo The purpose of this article is to analyse the institutional aspects of creating effective systems for monitoring and evaluations (M&E) in government-led rural development efforts in developing countries. We argue that the ultimate challenge of creating effective M&E systems for public policy is not only related to the supply of information and the delivery of new knowledge to policy makers, but more importantly to their demand for lessons learnt about the effects of earlier policies. The challenge, then, is for governments to construct institutional arrangements that support the transformation of policy lessons into policy actions. This article shows that the likelihood of this transformation is closely related to the capacity of institutions to deliver mechanisms for downward accountability and processes for organisational learning. We add to earlier work in this area by considering the conditions under which such a transformation process is more or less likely, given the severe power and information asymmetries that characterise the institutional context of many developing countries' national governments. We use the tools of institutional analysis to examine the incentive structures of the actors involved in two concrete field settings, and assess to what extent these actors are likely to take evaluations seriously. Copyright © 2004 John Wiley & Sons, Ltd. [source] Conjugated Macrocycles as Active Materials in Nonlinear Optical Processes: Optical Limiting Effect with Phthalocyanines and Related CompoundsTHE CHEMICAL RECORD, Issue 3 2002Michael Hanack Abstract An overview of the optical limiting (OL) processes in phthalocyanines and related compounds is presented, particularly a description of the synthesis and relevant optical properties of a series of axially substituted indium(III), titanium(IV), phthalo- and naphthalocyanines, and octaarylporphyrazines. Several techniques, such as transient absorption, Z-scan, and degenerate four-wave mixing, were used to assess the optical properties and OL performance of the investigated compounds. The versatility of the methods of organic synthesis leads to the achievement of effective systems in terms of OL performance through the appropriate combination and modulation of several structural components. The chemistry of the macrocycles here considered allows the variation of the different chemical features, such as the degree of electronic conjugation of the macrocycle and the nature of the ring substituents, the central atom, and the ligands attached to the central atom. © 2002 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 2: 129,148, 2002: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10024 [source] Rational Design of Sterically and Electronically Easily Tunable Chiral Bisimidazolines and Their Applications in Dual Lewis Acid/Brønsted Base Catalysis for Highly Enantioselective Nitroaldol (Henry) ReactionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2007Kuoyan Ma Abstract A new addition to the rational design of sterically and electrically easily tunable chiral bis(imidazoline) ligands from chiral amino alcohols has been developed. Vast structural variation of chiral bis(imidazoline) ligands can be simply achieved by the choice of both the 1,2-amino alcohol and its N-1 R1 substituent. A small library of chiral bisimidazolines (1,a,h) has been constructed. The method has provided an easy and simplified route to a diverse set of air-stable and water-tolerant chiral bis(imidazoline) ligands on 10,g scales. The dual Lewis Acid/Brønsted base catalytic system generated from the (S)- 1,a/Cu(OTf)2 complex and Et3N was able to catalyze Henry reactions between aldehydes and nitromethane effectively at room temperature, and also to tolerate a wide scope of aldehydes with excellent enantiomeric excesses. Not only aromatic aldehydes but also aliphatic aldehydes afforded the nitroalcohol products, with enantiomeric excesses in the 93,98,% range. This dual catalytic system is among the most effective systems so far reported for the asymmetric parent Henry reactions. This work also represents the first members of the class of chiral bisimidazolines to have been demonstrated to achieve excellent enantioselectivities. [source] | |||||||||||||||||||||||||||||||