Dendermonde - Kleinzand. Rapportage van het archeologisch proefsleuvenonderzoek - april 2010

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Evergem-nest. Archeologisch booronderzoek maart-april 2010

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Kluizen - Forelstraat. Archeologisch vooronderzoek 26/02/2010

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Gent-Hogeweg. Archeologisch proefsleuvenonderzoek 19/05 - 08/06/2010

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Возможности спиральной рентгеновской компьютерной томографии в дооперационной диагностике рака верхнего отдела желудка

Представлены данные о возможностях дооперационной диагностики распространенности опухолевого процесса при раке верхнего отдела желудка с помощью спирального рентгеновского компьютерного томографа, детально показаны методика выполнения исследования, ее достоинства и недостатки.Подано дані про можливості доопераційної діагностики розповсюдженості пухлинного процесу при раку верхнього відділу шлунка за допомогою спірального рентгенівського комп'ютерного томографа, детально показано методику виконання дослідження, її переваги й недоліки.The data about the capabilities of pre−operative diagnosis of tumor process generalization at cancer of the upper portion of the stomach using helical x−ray computed tomography are presented. The technique of the investigation as well as its advantages and disadvantages are described in detail

Fulvio Bianconi

Blanchaert Jean. Fulvio Bianconi. In: Sèvres. Revue de la Société des Amis du musée national de Céramique, n°15, 2006. pp. 102-110

Bioanalytical study of the bacterial transglycosylation reaction

Since the discovery of penicillin in the first half of the 20th century, antibiotics have contributed immensely to the improvement of general human health. However, soon after their mass introduction in medicine, the first signs of bacterial resistance towards these drugs have been noticed. Nowadays, the situation is alarming as more and more resistant strains are reported. One of the best known cases is the clinically important pathogen S. aureus of which 50 % of infections are caused by the MRSA strains which are resistant to all types of the β-lactam antibiotics. Only a few types of antibacterial therapeutics are left to treat patients infected with this strain. Therefore, research towards new antibacterial therapeutics is of the utmost importance. The bacterial cell wall and more specifically peptidoglycan, which already was the target of the first antibiotic, is still an interesting structure as not all processes involved in its production have been targeted. In S. aureus, the cell wall consists of a thick peptidoglycan layer into which wall-associated proteins and teichoic acids are incorporated. Peptidoglycan, the main component, is one giant net-shaped molecule. A structural degradation of their peptidoglycan is harmful to all bacteria and therefore an interesting target. It consists of strands of alternating units of N-acetyl-glucosamine (GlcNAc) and N-acetyl-muramic acid (MurNAc) and these strands are cross-linked by oligopeptides. The monomeric building block for the peptidoglycan is Lipid II. This is in essence a disaccharide unit to which a pentapeptide is attached, docked on an undecaprenyl pyrophosphate which serves as an anchor in the cell membrane. Lipid II is incorporated into peptidoglycan in two extracellular reactions. First the disaccharide unit is connected to a growing strand in a reaction called ‘transglycosylation’. The undecaprenyl pyrophosphate anchor is disconnected in this step. In a second phase, transpeptidation, the cross-linking of polysaccharide strands by their pentapeptides, occurs after the linear glycan strands are formed. Both reactions are catalyzed by a group of membrane-bound proteins called ‘penicillin binding proteins’ (PBPs). In contrast to the transpeptidation function of the PBPs, which is very intensively studied and is a well-known therapeutic target, the transglycosylation function has not led to any human therapeutic agents so far. This is not due to a shortage of potential candidates as there are many interesting compounds, such as moenomycin analogues, vancomycin analogues, ramoplanin, lantibiotics and many others… The lack of commercialized transglycosylation inhibitors is due to the lack of a good assay to test new compounds. The study towards transglycosylation has been hampered by the unavailability of the substrate, Lipid II. Since Lipid II became available due to efforts in chemical and enzymatic synthesis about a decade ago, a wide variety of assays and high-throughput screens have been developed. The difficulty in the development of such an assay lies in the absence of a UV-chromophore in Lipid II causing the need for other alternatives, mostly radioactive or fluorescent labeling. Since work with radioactive labels is tedious and time-consuming and the attachment of fluorescent groups might alter affinity of inhibitors towards Lipid II, a label-free assay would be most interesting. Therefore, the goal of this project was to develop a label-free LC/MS assay for the bacterial transglycosylation reaction which could be used in a later stage to test inhibitors. In this study, PBP2 from S. aureus is used because it is the most important transglycosylase in this species. Unfortunately, neither the PBP2 enzyme nor Lipid II were commercially available. PBP2 had to be recombinantly produced and Lipid II was produced enzymatically. Since our research group did not have the knowhow to fulfill these productions, recombinant production was done in collaboration with Dr. Tine Wyseure and Prof. Dr. Paul Declerck, and Lipid II was produced in collaboration with Dr. Eefjan Breukink. Both productions were completed in a reasonably short time without too many hurdles. The yield obtained for the enzyme as well as the substrate was satisfactory and estimated to be sufficient to complete the rest of the study. Before we could start incubations with the enzyme, we first needed an assay method for Lipid II. Therefore an LC/MS method was developed using only dilutions of the Lipid II stock solution in MeOH and water. The goal in this part of the method development was to create an assay that was able to separate Lipid II from the known related substances while keeping the run time short. Sensitivity of the method was optimized by selection of a suitable buffer and organic modifier. Also the SRM method was optimized. To allow reliable analyses, the method was already validated in this step. Validation was done according to ICH guidelines. This would be repeated on samples dissolved in incubation mixture after it had been optimized. No problems were encountered in the validation process. It was decided this method was suitable to monitor in vitro transglycosylation experiments. It was uncertain at first whether or not the recombinantly produced enzyme would be capable of catalyzing transglycosylation. Although correct sequences of the vector and the expressed protein were confirmed by Sanger sequencing and N-terminal sequence analysis respectively, the necessary, proper folding of the enzyme could only be confirmed by in vitro tests. After several attempts, finally conditions in which the enzyme is active, have been found. The influences of the composition of the incubation mixture and incubation conditions on enzyme activity have been evaluated and optimal conditions were selected. Under these circumstances repeatable enzyme activity was obtained. After the composition of the incubation mixture and the conditions had been determined, it was necessary to reevaluate the suitability of the previously developed LC/MS method. First of all, the occurrence of matrix effects was investigated using the post-extraction addition technique. Although the ionization suppression was found to be statistically significant, the effect was not too severe. The biggest problem encountered was the difference in response obtained between a sample dissolved in a mixture of MeOH and water and a sample in the incubation mixture. We reckoned this difference should be attributed to a co-precipitation of Lipid II with the PBP2 protein. As the problem could not be solved with a change in precipitation technique, the method was validated as such. It was necessary to ensure the decrease in substrate concentration could only be attributed to a PBP2-mediated transglycosylation activity. Therefore, the undecaprenyl-pyrophosphate leaving group in the transglycosylation reaction was successfully demonstrated in a test sample, whereas it could not be observed in the inactivated control. In another test, vancomycin was used to demonstrate inhibition of PBP2. In this way we confirmed that a decrease of substrate in the sample without inhibitor was due to transglycosylation. Initially, we were hoping to test the possibility of using moenomycin A as a quencher for the in vitro transglycosylation reaction. However, very soon it was noticed that moenomycin did not effectuate its inhibitory effect in contrast to our expectations. Despite several adaptations to the incubation mixture, all experiments with moenomycin A yielded the same result. This was unfortunate, because the development of moenomycin analogues is an important strategy in the field of transglycosylase inhibitors. Extracts of three plant species (Thymus sipyleus, Salvia verticillata and Salvia virgata) made with methanol, dichloromethane and hexane were evaluated for their possible inhibitory effect on transglycosylation.status: publishe

Localisation des lignes françaises du XVIIe siècle entre Ypres et Comines (Belgique): une contribution archéologique et géographique

Après la Paix de Nimègue, la France changea sa stratégie concernant sa frontière septentrionale et opta pour la construction d’une série de lignes de fortifications. Au contraire des villes fortifiées, ces lignes n’ont généralement pas été préservées dans le paysage et leur tracé est donc peu connu. Toutefois, nombreuses sont les cartes qui les mentionnent, au XVIIe et au XVIIIe siècle. Grâce à l’utilisation du SIG, il a été possible d’utiliser une série de cartes concernant les lignes entre Ypres et Comines et de les confronter avec les cartes modernes (cadastre, carte topographique). Ceci a permis d’identifier une quinzaine de points d’ancrage pour le tracé de cette ligne, rendant son parcours plus identifiable. Un seul contrôle sur le terrain, à la tarière, a été effectué et confirme la présence de la fortification. L’exercice montre tout le potentiel des cartes anciennes, lorsque l’on les utilise en SIG et les confronte avec les cartes modernes