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1.
Concluding remarks With this brief exposition of the areas covered in this special double issue on Eurotra, we shall now conclude our introduction. We hope that the volume will achieve its goals, as outlined above, at least to some extent. Certainly, much more could be said about a wide range of topics which have been covered in the lifetime or the project so far. For instance, these article, mainly written by linguists, deliberately neglect the software implementation and environment aspects of the prototype Eurotra Translation System, as well as a number of peripheral tools and components of the system that are available to the user, such as lexical data bases, text-handling mechanisms and the like. The reader interested in aspects of this kind is referred to Raw et al. 1989 for a very brief introduction, and to the Eurotra software team at the Commission of the European Communities (DG XIII, Luxembourg) for more details. However, one goal that we do hope to come close to achieving is to give a fair overview of the Eurotra linguistic theory of translation and the mainstream and sideline formalisms expressing variant versions of it. If we have come anywhere near achieving that, our gratitude is due to the numerous Eurotra colleagues who have supported us in preparing this volume, and to the editor of this journal. 相似文献
2.
A broadly cross-protective monoclonal antibody binding to Escherichia coli and Salmonella lipopolysaccharides 总被引:1,自引:0,他引:1
FE Di Padova H Brade GR Barclay IR Poxton E Liehl E Schuetze HP Kocher G Ramsay MH Schreier DB McClelland 《Canadian Metallurgical Quarterly》1993,61(9):3863-3872
During the last decade, episodes of sepsis have increased and Escherichia coli has remained the most frequent clinical isolate. Lipopolysaccharides (LPS; endotoxin) are the major toxic and antigenic components of gram-negative bacteria and qualify as targets for therapeutic interventions. Molecules that neutralize the toxic effects of LPS are actively investigated. In this paper, we describe a murine monoclonal antibody (MAb; WN1 222-5), broadly cross-reactive and cross-protective for smooth (S)-form and rough (R)-form LPS. As shown in enzyme-linked immunosorbent assay and the passive hemolysis assay, WN1 222-5 binds to the five known E. coli core chemotypes, to Salmonella core, and to S-form LPS having these core structures. In immunoblots, it is shown to react with both the nonsubstituted core LPS and with LPS carrying O-side chains, indicating the exposure of the epitope in both S-form and R-form LPS. This MAb of the immunoglobulin G2a class is not lipid A reactive but binds to E. coli J5, an RcP+ mutant which carries an inner core structure common to many members of the family Enterobacteriaceae. Phosphate groups present in the inner core contribute to the epitope but are not essential for the binding of WN1 222-5 to complete core LPS. Cross-reactivity for clinical bacterial isolates is broad. WN1 222-5 binds to all E. coli clinical isolates tested so far (79 blood isolates, 80 urinary isolates, and 21 fecal isolates) and to some Citrobacter, Enterobacter, and Klebsiella isolates. This pattern of reactivity indicates that its binding epitope is widespread among members of the Enterobacteriaceae. WN1 222-5 exhibits biologically relevant activities. In vitro, it inhibits the Limulus amoebocyte lysate assay activity of S-form and R-form LPS in a dose-dependent manner and it neutralizes the LPS-induced release of clinically relevant monokines (interleukin 6 and tumor necrosis factor). In vivo, WN1 222-5 blocks endotoxin-induced pyrogenicity in rabbits and lethality in galactosamine-sensitized mice. The discovery of WN1 222-5 settles the long-lasting controversy over the existence of anti-core LPS MAbs with both cross-reactive and cross-protective activity, opening new possibilities for the immunotherapy of sepsis caused by gram-negative bacteria. 相似文献
3.
During a study of natural food colours, a simple and reliable high-performance liquid chromatography system was developed for use with cochineal and annato. An isocratic mobile phase, consisting of methanol and 6% aqueous acetic acid, resolved bixin and norbixin, while a gradient system was used to separate carminic acid and the annato compounds. The carminic acid contents of cochineal extract, carmine and carmine hydrosoluble were determined using an isocratic mobile phase (40:60, v/v). The detection limit for carminic acid in the various products was approximately 100 ng/g. Carminic acid was determined quantitatively in fruit beverages, yogurt and candies. It was demonstrated that, because of decomposition, carminic acid was not suitable for use in candies when manufacturing temperatures above 100 degrees C were required. Most membrane filters are not suitable for use with cochineal solutions, but a cellulose membrane filter did not adsorb carminic acid and was used successfully to remove impurities from water-based cochineal products and food extracts containing carminic acid. 相似文献
4.
KW Scheller J G?rres JG Ross M Wiescher R Harkewicz DJ Morrissey BM Sherrill M Steiner NA Orr JA Winger 《Canadian Metallurgical Quarterly》1994,49(1):46-50
The shortage of suitable liver donors for children has motivated the use of ABO-incompatible (ABO-I) grafts for transplantation in urgent situations. However, survival after ABO-I liver grafts has been reported at about 30% as compared with 80% in cases of ABO-identical or -compatible liver grafts. This difference has been attributed to antibody-mediated, hyperacute or chronic liver rejection, due to preformed ABO antibodies (alloantibodies). In this study, we report our results with ABO-I livers in children without alloantibodies at the time of transplantation. From January 1988 to June 1993, 143 OLT were performed in 122 children. Eight children received 8 ABO-I liver grafts. Of these, 7 patients were included in the study. All 7 were alloantibody free before OLT. Five children were spontaneously alloantibody free, while in 2 children, the plasma alloantibodies were eliminated before and after transplantation using intravenous infusion of specific blood group antigens of the donor blood group (soluble antigens). Immunosuppression consisted of a triple-drug treatment combining CsA, AZA, and steroids. The follow-up period was between 10 and 48 months. One child died from a surgical complication. Six children survived, but 1 died 10 months later from intestinal obstruction. There were no graft losses and no episodes of hyperacute or chronic rejection. The graft and patient survival rate was 71%. There was a 28% incidence of rejection, but all were mild (requiring steroid boluses only). Our results suggest that the absence of ABO alloantibodies at the time of and after transplantation can protect ABO-I liver grafts against antibody-mediated rejection, whether hyperacute or chronic, and that soluble antigens are effective in eliminating alloantibodies in children. 相似文献
5.
6.
M. Steiner 《Journal of Low Temperature Physics》2004,135(5-6):545-578
The ordering of nuclear spins takes place at extremely low temperatures because of the weakness of the interactions between their magnetic moments. Neutron scattering is the traditional and unique method to study the collective ordering of magnetic moments. The combination of the problem (nuclear spin ordering) and the method (neutron scattering) leads to new insight into the many body behaviour of the nuclear spin system and into some of the long standing general questions of the cooperative behaviour of magnetic systems. We describe neutron scattering studies on the nuclear spin systems in Cu and Ag at nano- and subnanokelvin temperatures as an example of a very successful international collaboration based on the work performed at the Low Temperature Laboratory, in the Helsinki University of Technology in Otaniemi. The collaboration was initiated by Olli V. Lounasmaa. 相似文献
7.
Large, uncoated copper and zinc roofs cause environmental problems if their runoff is infiltrated into the underground or discharged into receiving waters. Since source control is not always feasible, barrier systems for efficient copper and zinc removal are recommended in Switzerland. During the last few years, research carried out in order to test the performance of GIH-calcite adsorber filters as a barrier system. Adsorption and mass transport processes were assessed and described in a mathematical model. However, this model is not suitable for practical design, because it does not give explicit access to design parameters such as adsorber diameter and adsorber bed depth. Therefore, for e.g. engineers, an easy to use design guideline for GIH-calcite adsorber systems was developed, mainly based on the mathematical model. The core of this guideline is the design of the depth of the GIH-calcite adsorber layer. The depth is calculated by adding up the GIH depth for sorption equilibrium and the depth for the mass transfer zone (MTZ). Additionally, the arrangement of other adsorber system components such as particle separation and retention volume was considered in the guideline. Investigations of a full-scale adsorber confirm the successful application of this newly developed design guideline for the application of GIH-calcite adsorber systems in practice. 相似文献
8.
R Albrecht TC Awes C Baktash P Beckmann F Berger R Bock G Claesson G Clewing L Dragon A Eklund RL Ferguson A Franz S Garpman R Glasow HA Gustafsson HH Gutbrod J Idh P Jacobs K Kampert BW Kolb P Kristiansson IY Lee H Loehner I Lund FE Obenshain A Oskarsson I Otterlund T Peitzmann S Persson F Plasil AM Poskanzer M Purschke H Ritter S Saini R Santo HR Schmidt T Siemiarczuk SP Sorensen E Stenlund ML Tincknell GR Young 《Canadian Metallurgical Quarterly》1991,44(6):2736-2752
9.
FE Nargang KP Künkele A Mayer RG Ritzel W Neupert R Lill 《Canadian Metallurgical Quarterly》1995,14(6):1099-1108
MOM22 is a component of the protein import complex of the mitochondrial outer membrane of Neurospora crassa. Using the newly developed procedure of 'sheltered disruption', we created a heterokaryotic strain harboring two nuclei, one with a null allele of the mom-22 gene and the other with a wild-type allele. Homokaryons bearing the mom-22 disruption could not be isolated, suggesting that mom-22 is an essential gene. The mutant nucleus can be forced to predominate in the heterokaryon through the use of specific nutritional and inhibitor resistance markers. Cultivation of the heterokaryon under conditions favoring the mutant nucleus resulted in selective depletion of MOM22. MOM22-depleted cells did not grow and contained mitochondria with an altered morphology and protein composition. Protein import into isolated, MOM22-depleted mitochondria was abolished for most precursor proteins destined for all subcompartments. In contrast, precursors of MOM19, MOM22 and MOM72 became inserted normally into the outer membrane, defining a novel MOM22-independent import pathway which remained intact in mutant mitochondria. Furthermore, the specific binding of the ADP/ATP carrier to the outer membrane was unaffected, but subsequent transport across the outer membrane did not occur. Our data show that MOM22 is an essential component of Neurospora cells specifically required for the biogenesis of mitochondria. 相似文献
10.
EA Scodeller SG Tisminetzky F Porro M Schiappacassi A De Rossi L Chiecco-Bianchi FE Baralle 《Canadian Metallurgical Quarterly》1995,13(13):1233-1239
The principal neutralizing domain, IGPGRAF sequence, from the V3-loop of HIV-1 was inserted in two positions on the surface of the protein that makes up the capside shell of the insect Flock House Virus. The hybrid proteins were expressed in insect cells via recombinant baculoviruses. Three different hybrids were used as immunogens: two with a single copy of the insert in different positions of the carrier protein and a third with two copies of the insert at the same positions as before. All hybrid proteins induced strong and broad specific immune response in guinea pigs against different V3-loop sequences. However, only one of the hybrid proteins was able to induce a strong neutralizing response against MN and IIIB HIV-1 isolates. Our results demonstrate that a very short peptide sequence of HIV-1 can constitute a valuable immunogen able to induce a neutralizing response if presented to the immune system in the context of the FHV capsomer structure. 相似文献