Montpellier. Fac. pharm. Thèse univ. 1937.

Quartz crystal microbalances, (QCM), are high frequency oscillators, capable of nanogram mass resolution in both air and liquid environments. ~ work has produced data showing the feasibility of using the QCM for monitoring interactions in liquids for several types of systems and has allowed comparison with surface plasmon resonance (SPR) where appropriate. Bulk phase changes in viscosity and density have been used in the development of a QCM agglutination assay for the Staphylococcus epidermidis infection which has reduced diagnosis periods by a factor of twelve. Direct interactions at the crystal electrode have been employed when studying bacterial adhesion to protein treated gold surfaces. It was shown that suspensions containing as little as I x 10-2 cellsml-1 could be recognised using the QCM system. A novel boronic acid - vicinal diol interaction mechanism has been employed as a model for receptor-ligand binding. New boronic acid disulphide and short chain thiol derivatives have been synthesised and the formation of self assembled monolayers of the~e compounds monitored, both on the gold QCM electrodes and on the gold films of SPR slides, the assembly mechanism being shown to fit a two stage model shown by other workers for straight chain thiols. Monolayer orientation was confirmed using SPR, by the binding of a range of saccharides and the diol containing enzyme cofactor nicotinamide adenine dinucleotide. The enzymes lactate dehydrogenase and glucose-6-phosphate dehydrogenase have been shown to interact with bound NAD using both a novel flow injection system with QCM detection and SPR. The low molecular weight saccharide, glucose, was shown to bind reversibly to GDH on the surface of a QCM and the potential for kinetic stu4ies recognised. This was taken one step further with a preliminary investigation into sensing within real fluids, using diluted and spiked human seruin samples.

Pacific shrimp (Pandalus jordani) was washed repeatedly and the eluted bacteria were enumerated and identified. Selected isolates were tested for their adhesive properties. Washing reduced the microbial load by 3.84 to 42.04%. The bacteria which most resisted wash-off were Staphylococcus and Pseudomonas spp. The easiest to wash off was Flavobacterium spp. In higher-count samples, Moraxella and/or Lactobacillus spp. washed off readily, but they still constituted large proportions of the residual bacteria on shrimp. Adhesiveness, measured by hydrophobic interaction with octane, showed 43.3% change in absorbance by Staphylococcus spp., followed by 21.5% by Moraxella spp., and Arthrobacter spp. at 13.5%. Pseudomonas spp. showed only 5.7% change in absorption. Attachment, measured by hanging glass cover slips in broth, however, showed Pseudomonas and Staphylococcus spp. to have the greatest ability to adhere, with 0.47 and 0.46% attachment, respectively. Moraxella spp. showed the least ability to adhere to glass (.02%), followed by Lactobacil lus spp. at 0.11%. Arthrobacter and Flavobacterium spp. adhered at 0.30 and 0.37% levels, respectively. Attachment of Pseudomonas spp. to glass was the least affected by media composition, temperature, or presence of a surface-active agent (sodium hexametaphosphate). Staphylococcus spp., on the other hand, attached most strongly under optimum growth conditions but were most affected by varying growth conditions, temperature, and presence of a metabolic inhibitor (sodium hexametaphosphate). This indicates that the adhesive ability of Staphylococcus spp. is directly related to its metabolic activity, while Pseudomonas spp. is less sensitive to changes in metabolism and may depend on motility for adhesion. Bacteria that could adhere strongly on solid surfaces (Pseudomonas and Staphylococcus spp.) tend to be found in greater proportions and, hence, contribute more to the spoilage of shrimp. / Graduation date: 1983

Thesis (M.S.)--University of Wisconsin--Madison, 1944. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [42-45]).

no abstract provided by author / Master of Science

Myocardial infarction (MI) is an acute life-threatening disease with a high incidence worldwide. Aim of this study was to test lectin-carbohydrate binding-induced red blood cell (RBC) agglutination as an innovative tool for fast, precise and cost effective diagnosis of MI. Five lectins (Ricinus communis agglutinin (RCA), Phaseolus vulgaris erythroagglutinin (PHA), Datura stramonium agglutinin (DSA), Artocarpus agglutinin (ArA), Triticum agglutinin (TA)) were tested for ability to differentiate between agglutination characteristics in patients with MI (n = 101) or angina pectoris without MI (AP) (n = 34) and healthy volunteers (HV) as control (n =68) . RBC agglutination was analyzed by light absorbance of a stirred RBC suspension in the green to red light spectrum in an agglutimeter (amtec, Leipzig, Germany) for 15 min after lectin addition. Mean cell count in aggregates was estimated from light absorbance by a mathematical model. Each lectin induced RBC agglutination. RCA led to the strongest RBC agglutination (~500 RBCs/aggregate), while the others induced substantially slower agglutination and lead to smaller aggregate sizes (5-150 RBCs/aggregate). For all analyzed lectins the lectin-induced RBC agglutination of MI or AP patients was generally higher than for HV. However, only PHA induced agglutination that clearly distinguished MI from HV. Variance analysis showed that aggregate size after 15 min. agglutination induced by PHA was significantly higher in the MI group (143 RBCs/ aggregate) than in the HV (29 RBC-s/aggregate, p = 0.000). We hypothesize that pathological changes during MI induce modification of the carbohydrate composition on the RBC membrane and thus modify RBC agglutination. Occurrence of carbohydrate-lectin binding sites on RBC membranes provides evidence about MI. Due to significant difference in the rate of agglutination between MI > HV the differentiation between these groups is possible based on PHA-induced RBC-agglutination. This novel assay could serve as a rapid, cost effective valuable new tool for diagnosis of MI.

Les adénovirus ont une double nature, soit comme pathogène omniprésent qui peuvent occasionnellement causer des maladies soit comme vecteurs utilisés de transfert de gène. À nos connaissances, les 30 premières minutes depuis la liaison au récepteur jusqu'à l'arrivée au pore nucléaire sont identiques pour le pathogène comme pour le vecteur. L'objectif de ma thèse était de comprendre les mécanismes impliqués dans la liaison au récepteur, l'internalisation, l'échappement et le trafic endosomal vers le MTOC. J'ai d'abord étudié le mécanisme impliqué dans l'hémagglutination des virus à tropisme pour CAR et à tropisme pour SA. J'ai identifié la présence de CAR sur les érythrocytes humains et montré qu'il était le principal responsable de l'agglutination induite par les virus à tropisme pour CAR. De plus, j'ai montré que la présence de CAR sur les érythrocytes pouvait piéger le virus dans le sang et ainsi empêcher l'infection au niveau du foie. Dans un deuxième temps, j'ai participé à la caractérisation du rôle de la protéine VI et la translocation du virus au MTOC. Nous avons montré que Nedd4 était impliqué dans le ciblage du virus au MTOC via l'ubiquitination de la protéine VI. Enfin, j'ai travaillé sur le neurotropisme de CAV-2 et caractérisé sa localisa tion subcellulaire au niveau des synapses. J'ai montré qu'une partie de CAR était localisée dans des radeaux lipidiques à la synapse et que CAV-2 entrait via la voie de recyclage des vésicules synaptiques. / Adenoviruses have a dual nature as ubiquitous pathogens that occasionally cause life-threatening disease and their use as gene transfer vectors. To the best of our current knowledge, the first 30 min from binding to nuclear pore docking of both wild-type virus and vector are identical. The goal of my thesis is to understand different mechanisms involved in receptor binding, internalization, endosomal escape and trafficking to the MTOC. First I studied the mechanism involved in hemagglutination of CAR-tropic and SA-tropic viruses. I identified the presence of CAR on human erythrocytes and showed that it was the main responsible for the agglutination mediated by CAR-tropic viruses. Moreover, I show that CAR on erythrocytes can sequester virus in the bloodstream and block liver infection. In a second part I participated to the characterization of the role of the protein VI and the translocation of HAd to the MTOC. We showed that Nedd4 was involved in the targeting of the virus to MTOC through ubiquitination of this protein VI. Finally, I worked on the neurotropism of CAV-2 and characterize its subcellular localization at the synapse. I showed that a part of CAR was localized in lipid raft at the synapse and enter through the synaptic vesicle-recycling pathway.

by Wong Dart-man. / Bibliography: leaves 107-114 / Thesis (M.Phil.)--Chinese University of Hong Kong, 1982

För att undvika komplikationer vid blodtransfusioner fenotypas blodgivarens blod med avseende på kliniskt relevanta blodgruppsantigen. Fenotypning innebär att erytrocytantigen påvisas, vilket kan utföras med bland annat rör- eller gelkortsteknik. Dessa tekniker bygger på antigen-antikroppsreaktioner, agglutination. Agglutinat kan uppstå direkt när antikroppar binder samman erytrocyter eller uppstå sekundärt när antihumanglobulin reagerar med antikroppar bundna till erytrocyter. Syftet med studien var att jämföra rörteknik och gelkortsteknik för fenotypning avantigenerna RhC, -c, -E, -e inom Rh-systemet samt antigenerna inom Kell- (K), Duffy-(Fya)och Kidd-systemen (Jka). Detta med avseende på säkerhet, tid, ekonomi samt att utföra en validering av fenotypning med gelkortsteknik. Blod från 80 blodgivare fenotypades manuellt (direkt agglutination och indirekt antihumanglobulinteknik) med rör- och gelkortsteknik.Resultaten visade ingen skillnad mellan rör- och gelkortsteknik avseende de i studien fenotypade erytrocytantigen. Resultaten visade att rörtekniken är ett kostnadseffektivt verktyg för fenotypning. Totalkostnaden för fenotypning av 20 blodprover var 1157,06 SEK med rörteknik respektive 1337,11 SEK med gelkortsteknik. Men tack vare högre säkerhet, ökad effektivitet och bättre prestanda är gelkortsteknik att föredra även om den medför endast en ringa merkostnad. Gelkortstekniken ger en ökad säkerhet för både den som utför analysen genom minskad smittrisk samt för patienten eftersom tolkningsosäkerheten och tolkningsdifferensen minskar. Ett byte från rörteknik till gelkortsteknik är därför att rekommendera för blodcentralen vid länssjukhuset i Kalmar.

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