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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Régulation du cycle vésiculaire et de l’approvisionnement en GABA des interneurones de l’hippocampe en fonction de l’activité / Regulation of GABA supply and vesicular cycle in function of activity of hippocampal interneurons

Bonet, Laurine 30 September 2016 (has links)
Les interneurones GABAergiques dans l’hippocampe forment de petites populations diverses de neurones inhibiteurs contrôlant le transfert d’informations dans de larges ensembles de cellules principales. Ils compensent leur infériorité numérique par de vastes arborisations axonales capables de maintenir une libération vésiculaire de GABA à haute fréquence, et d’ajuster précisément la balance entre excitation et inhibition pour différents régimes d’activité du réseau. Les petites synapses centrales contiennent un nombre limité de vésicules synaptiques dont le recyclage par endocytose est essentiel au maintien de la transmission pendant une activité répétée. Le remplissage en GABA de ces vésicules recyclées est dépendant d’un approvisionnement des terminaisons en GABA suffisant pour faire face à la demande de recyclage créée par l’activité. Nos résultats mettent en évidence de nouveaux mécanismes d’adaptation de l’approvisionnement aux besoins imposés par le recyclage vésiculaire selon le régime d’activité, ainsi qu’un couplage direct entre le cycle de neurotransmetteurs et le cycle vésiculaire. Nous montrons que les transporteurs de glutamine sont responsables d’une potentialisation de l’approvisionnement des varicosités en GABA lors d’une activité répétée, probablement par une augmentation du nombre de ces transporteurs à la membrane. En développant et en utilisant des paradigmes expérimentaux nouveaux, nous montrons que la régulation métabolique du cycle vésiculaire passe par une adaptation du pool de vésicules recyclantes à la disponibilité en neurotransmetteurs. La nature du senseur de cette régulation et sa localisation cytosolique ou luminale restent à déterminer / In the hippocampus, GABAergic interneurons represent only 10% of the neuronal population but are able to synchronize the activity of large neuronal networks. They compensate their numerical inferiority by a large axonal arborization to sustain synaptic activity at high frequency and adjust the balance between excitation and inhibition for different regime of activity. Since small central synapses contain a limited pool of vesicles, their recycling by endocytosis is essential to maintain transmission during repeated activity. The filling of recycling vesicles with GABA is dependent on its supply in terminals which should be adjusted to the demand imposed by vesicular recycling. Our results reveal new transporter mechanisms that adapt GABA supply to neuron activity, suggesting a direct coupling between the neurotransmitter and the vesicle cycles. We show that high recycling activity increases GABA supply, probably by increasing the number of glutamine transporters at the membrane. By developing and using FM5-95 and VGAT-pHluorin with a new experimental paradigm, we provide evidence for a metabolic regulation of the vesicle cycle that involves a dynamic adaptation of the recycling pool to the neurotransmitter availability. The nature of the sensor of this regulation and its cytosolic or luminal location remain to be determined.
262

Utredning av intermodala transporter för materialtransport inom byggbranschen / Investigation of intermodal transports for material transport in the construction industry

Väinölä, Niclas, Wong, Bengt January 2019 (has links)
Rapporten undersöker skillnaden mellan vägtransporter och intermodala transporter. Detta görs bland annat genom en totalkostnadsanalys vilket undersöker kostnader relaterade till transportprocessen och även miljöpåverkan genom utsläpp de olika transportmetoderna bidrar med och diskuterar även kringliggande faktorer som påverkar valet av transportmetod. Det visar sig att vägtransporter är det billigare alternativet men de bidrar även med mycket större miljöpåverkan än Intermodala transporter.
263

Transportkostnader i HKScans distribution : En utredning av vilka faktorer som driver transportkostnader och hur de kan påverkas / Transport costs in the distribution of HKScan : A study of the factors that drive transport costs and how they can be affected

Antonsson, Viktor, Ek, Johanna January 2017 (has links)
Denna rapport innehåller en fallstudie av företaget HKScan och fokuserar på deras interna hantering av transporter ut till kunderna. Eftersom HKScan verkar i en konkurrensutsatt bransch med små marginaler så är det viktigt att varenda krona används på ett bra sätt. Transporter är en aktivitet som sällan undersöks eftersom det är en operativ aktivitet som är fristående från övrig verksamhet. Det har dock visat sig att även om olika funktioner i ett företag traditionellt styrs separat så finns det starka kopplingar mellan transporter och funktioner som sälj, marknad, inköp, ekonomi, personaladministration och produktion. Denna studies syfte var därför att undersöka vilka faktorer som påverkar transportkostnaderna och ge förslag på hur transportkostnaderna på sikt kan minskas. Undersökningen av vilka faktorer som påverkar transportkostnaderna genomfördes i flera steg. Först sammanställdes de faktorer som nämns i teorin vilket kompletterades med de faktorer som Supply Chain-funktionen på HKScan trodde påverkade transportkostnaderna. Detta resulterade i en modell med 18 möjliga påverkande faktorer som sedan avgränsades beroende på vad HKScan mäter och vad som ansågs relevant att undersöka. Denna avgränsade lista bestod av sju drivare som sedan undersöktes med hjälp av en multipel regressionsanalys. I denna analys kunde det matematiskt bevisas att faktorerna vikt per transportkolli, transporttemperatur, kvantitet, avstånd samt vilken typ av kund som transporten gick till påverkar transportkostnaden både på sändningsnivå och per transportkolli. Efter att dessa drivare identifierats så hölls intervjuer för att undersöka vilka funktioner som har störst möjlighet att påverka dem och därför i förlängningen även kan påverka transportkostnaden direkt. Dessa intervjuer visade att det främst är funktionerna för sälj och Supply Chain som direkt kan påverka transportkostnaden. Även marknad och produktion har möjlighet att påverka transportkostnaden på ett indirekt sätt. Slutligen genomfördes intervjuer med personal från de berörda funktionerna för att undersöka på vilket sätt medvetenheten och styrningen av transportkostnaderna kan förbättras. Detta resulterade i ett stort antal förslag där det mest frekvent förekommande var en kontinuerlig uppföljning av transportkostnaderna. Denna uppföljning ska inte bara vara på nivån att transportkostnaderna varit dyra utan gå djupare och peka på vilka mönster i beställningar och transporter som gett upphov till den högre kostnaden. Om denna uppföljning ska ske manuellt eller med hjälp av ett automatiserat verktyg finns det olika åsikter om men personalen känner genomgående de behöver öka medvetenheten om vad som påverkar transportkostnaderna för att kunna sänka dem. / This report contains a case study of the company HKScan and focuses on their internal handling of transports to customers. As HKScan operates in a competitive industry with small margins, it is important that all money is used in the best way. An activity that costs money but rarely is investigated is the transportation since it is seen as a very operative activity. It has, however, been found that although different functions of a company are traditionally controlled separately, there are strong links between transports and functions such as sales, marketing, purchasing, finance, human resource management and production. The purpose of this study was therefore to investigate which factors that affect transport costs and provide suggestions on how transport costs can be reduced. The study of which factors that affect transport costs was carried out in several stages. First, factors mentioned in the theory were compiled and complemented by the factors that the Supply Chain department at HKScan believed could affect the cost. This resulted in a list of 18 possible influencing factors that were then demarcated depending on what HKScan measures and which was considered relevant to investigate. This demarcated list consisted of seven factors, which were then investigated using a multiple regression analysis. From this analysis, it could be mathematically proven that the parameters quantity, distance, weight per transport package, temperature, and the type of customer to which the transport went, affects the transport cost both at the shipping level and per transport package. After these drivers had been identified, interviews were held to investigate which departments have the greatest potential to influence them and, in the long run, affect transport costs. These interviews showed that it was primarily the sales and Supply Chain departments that affect the shipping costs, even though market and production have a more indirect impact. Finally, interviews were conducted with staff from the relevant departments to investigate how awareness and management of transport costs can be improved. This resulted in a large number of proposals where the most frequent one mentioned was a continuous follow-up on transport costs. This follow-up should point out which patterns in orders and shipments that gave rise to the higher cost. If this follow-up is to be done manually or by means of an automated tool, there are different views, but the staff feels that in order to reduce transport costs, they need increased awareness of what affects them. / <p>Observera att alla siffror och resultat i rapporten är modifierade och speglar inte det verkliga resultatet.</p>
264

O transportador ABC de Trypanosoma cruzi TcABCG1 potencialmente envolvido na resistência a benznidazol: características e filogenia. / The ABC transporter of Trypanosoma cruzi TcABCG1 potentially involved in benznidazole resistance: characteristics and phylogeny.

Carvalho Junior, Jaques Franco de 29 April 2014 (has links)
Benznidazol (BZ), fármaco utilizado para o tratamento da doença de Chagas, apresenta eficácia limitada na fase crônica da doença. Falhas terapêuticas foram atribuídas majoritariamente a diferenças na suscetibilidade a BZ entre as cepas do T. cruzi. Resultados prévios de nosso grupo indicam que o gene de um transportador ABC da subfamília G, TcABCG1, encontra-se super-expresso em cepas resistentes a BZ. Transportadores ABCG foram associados a resistência a drogas em vários organismos. O objetivo central do presente estudo foi caracterizar o gene TcABCG1 em cepas de diferentes linhagens e cuja suscetibilidade a BZ foi definida. A sequência do gene TcABCG1 (1.998 pb) de 14 cepas foi determinada. Observamos algumas variações de aminoácidos na proteína ABC entre as cepas. Análises genealógicas de TcABCG1 definiram quatro clados (TcI, TcII, TcIII e Tcbat). Os dois haplótipos das cepas híbridas TcV e TcVI agruparam com os clados TcII e TcIII. Dados de imunofluorescência indireta em epimastigotas indicam que TcABCG1 está localizado em vesículas intracelulares. / Benznidazole (BZ), drug employed for Chagas disease treatment, has limited efficacy in the chronic phase of the disease. Treatment failures have been attributed mostly to differences in BZ susceptibility among T. cruzi strains. Previous data from our group indicate that one ABC transporter gene of the G subfamily, named TcABCG1, is overexpressed in BZ-resistant strains. ABCG transporters have been associated to drug resistance in several organisms. The central goal of the present study was to characterize TcABCG1 gene in strains belonging to different lineages and of defined BZ susceptibility. TcABCG1 gene sequence (1,998 bp) of 14 strains was determined. Few amino acid substitutions were detected in the ABC transporter protein among the strains. Genealogic analyses of TcABCG1 showed four distinct clades (TcI, TcII, TcIII and Tcbat). The two haplotypes of TcV and TcVI hybrid strains clustered with TcII and TcIII clades. Indirect immunofluorescence analysis in epimastigote forms indicated that TcABCG1 is localized to intracellular vesicles.
265

Estudo de transportador de poliaminas, PotD, e seus híbridos como antígenos vacinais contra Streptococcus pneumoniae. / The study of the polyamine transporter, PotD, and it hybrids as vaccine antigens against Streptococcus pneumoniae.

Converso, Thiago Rojas 10 February 2017 (has links)
A Proteína Transportadora de Poliaminas (PotD) é um antígeno importante para a virulência de Streptococcus pneumoniae in vivo, capaz de proteger camundongos imunizados contra infecção sistêmica, além de reduzir a colonização da nasofaringe dos animais. Porém, visando ampliar a cobertura vacinal, a combinação com outros antígenos da bactéria se faz necessária. Este trabalho teve como objetivo aprofundar o estudo sobre a resposta imune gerada contra a proteína PotD, sozinha ou em fusão com duas outras proteínas pneumocócicas: o derivado de Pneumolisina, PdT, e a proteína de superfície de pneumococo A (PspA). Para tanto, os genes potD, pdT e pspA foram clonados e expressos, sozinhos ou fusionados, gerando as proteínas híbridas rPotD-PdT e rPspA-PotD. As proteínas recombinantes e os híbridos foram utilizados na imunização subcutânea de camundongos BALB/c, gerando elevados níveis de anticorpos. O soro dos animais imunizados foi capaz de reconhecer e se ligar à superfície de diferentes isolados de pneumococos, e de ampliar a fagocitose da bactéria por células peritoneais murinas in vitro. Em todos os ensaios, os híbridos se mostraram mais eficazes do que as proteínas isoladas, induzindo anticorpos capazes de potencializar a fagocitose dos pneumococos. A resposta imune celular foi caracterizada pela produção de INF-&#947;, IL-2 e IL-17 pelos esplenócitos, e um aumento na produção de NO pelos fagócitos peritoneais dos animais imunizados. Apesar dos resultados promissores in vitro, a proteína rPotD-PdT não foi capaz de induzir proteção em nenhum dos modelos avaliados; em contraste, a fusão rPspAPotD foi capaz de proteger os camundongos contra sepse por dois isolados virulentos de pneumococo, além de reduzir a colonização na nasofaringe. Por fim, demonstramos que a adição das poliaminas transportadas por PotD, espermidina e putrescina, à cultura de pneumococos interfere na formação de biofilme in vitro. Cnsiderando o importante papel da formação de biofilmes na colonização, este resultado sugere um possível mecanismo de ação da PotD durante a colonização por pneumococo. Em conjunto, os resultados deste estudo sugerem que a utilização de uma formulação híbrida, rPspA-PotD, compreende uma estratégia vacinal promissora, capaz de proteger contra colonização e sepse pneumocócica, pela produção de anticorpos opsonizantes e ativação de citocinas protetoras, como IL-17. / Polyamine Transporter D (PotD) is an important antigen for Streptococcus pneumoniae virulence in vivo, protecting immunized mice against systemic infection and reducing the bacterial load in the nasopharynx of immunized animals. However, in order to extend vaccine coverage, the combination of PotD with other antigens of the bacterium is required. The present study aimed at expanding the investigation of the immune response generated against PotD alone or fused with two other pneumococcal proteins: the Pneumolysin derivative, PdT and Pneumococcal Surface Protein A (PspA). Therefore, the potD, pdt and pspA genes were cloned and expressed, either alone or in fusion, generating the hybrid proteins rPotD-PdT and rPspA-PotD. The recombinant proteins and hybrids were used for subcutaneous immunization of BALB/c mice, generating high levels of antibodies. Sera from immunized animals were able to recognize and bind onto the surface of different pneumococcal strains, and to enhance phagocytosis of the bacterium in vitro. In all tests, the hybrids were more effective than the isolated proteins. The cellular immune response was characterized by the production of INF-&#947;, IL-2 and IL-17 by splenocytes and increased production of NO by peritoneal cells of the immunized animals. Despite promising results in vitro, rPotD-PdT protein was not able to induce protection in any of the tested challenge models. In contrast, rPspA-PotD fusion was able to protect mice against sepsis with two virulent isolates of pneumococcus and led to reduction in bacterial loads in the nasopharynx of challenged animals. Finally, we demonstrate that the addition of exogenous polyamines, spermidine, and putrescine, in the pneumococcal culture interfered with biofilm formation in vitro. Considering the important role of biofilm formation for successful colonization, this result suggests a possible mechanism of action of PotD during colonization by pneumococcus. Taken together, the results suggest that the use of the hybrid rPspA-PotD comprises a promising vaccine strategy, able to protect against colonization and pneumococcal sepsis, through the production of opsonizing antibodies and activation of protective cytokines, such as IL-17.
266

Caractérisation d’un transporteur ABC d’antibiotiques de Streptococcus pneumoniae, PatA-PatB / Characterization of PatA-PatB, a Streptococcus pneumoniae ABC transporter involved in antibiotic resistance

Mathieu, Khadija 17 April 2019 (has links)
Au cours des dernières décennies, une augmentation non négligeable du phénomène de résistance aux antibiotiques des bactéries a été observée. Ces bactéries possèdent plusieurs mécanismes de résistance parmi lesquels l’utilisation de transporteurs de type MDR (MultiDrug Resistance) dont certains appartiennent à la famille des transporteurs ABC (ATP-Binding Cassette). Les transporteurs ABC sont des protéines membranaires et ubiquitaires qui possèdent une topologie commune avec deux domaines transmembranaires et deux domaines cytoplasmiques. Les transporteurs ABC de type exportateur permettent le transport de molécules à l’extérieur de la cellule en utilisant l’énergie fournie par l’hydrolyse de l’ATP. PatA-PatB est un transporteur ABC de Streptococcus pneumoniae, un pathogène humain responsable de pneumonies et de méningites. Cette protéine est impliquée dans la résistance de ce pathogène à des antibiotiques de types fluoroquinolones. Pour étudier son mécanisme moléculaire, nous avons optimisé la surexpression fonctionnelle de ce transporteur chez Escherichia coli. Ainsi, nous avons pu caractériser son activité de transport de drogues et son activité d’hydrolyse de nucléotides. Ces expériences ont révélé que PatA-PatB a la particularité d’utiliser préférentiellement le GTP comme source d’énergie, contrairement aux autres membres de cette famille. Afin d’identifier l’origine de cette propriété au niveau moléculaire, des expériences de mutagénèse dirigée ont été effectuées et nous avons ainsi identifié deux simples mutants qui transportent les drogues aussi bien avec du GTP que de l’ATP / The excessive use of antibiotics during the past decades led to the amplification of multidrug resistance in pathogenic bacteria. Bacteria have developed several mechanisms of antibiotic resistance. One of them involves the antibiotic efflux by MDR (MultiDrug Resistance) transporters, some of which belong to the ABC (ATP-Binding Cassette) transporter family. ABC transporter are ubiquitous membrane proteins with a conserved topology comprising four domains : two «TransMembrane Domain» and two cytoplasmic domains named « Nucleotide-Binding Domain ». ABC exporters expel drugs outside the bacteria using the energy of ATP hydrolysis. PatA-PatB is an ABC transporter from Streptococcus pneumoniae, a human pathogen bacterium responsible for pneumonia and meningitis. This protein is involved in S. pneumoniae resistance against fluoroquinolone antibiotics. To study the molecular mechanism, we optimized the functional expression of this transporter in Escherichia coli. Then, we characterized its drug transport activity and its nucleotide hydrolysis activity. These experiments showed that PatA-PatB, in contrast to other members of the ABC superfamily, preferentially uses GTP as energy supply. To identify the origin of this property at a molecular level, mutagenesis experiments were performed and we identified two mutants capable of an even drug transport with ATP and GTP
267

Metabolização de açúcares em linhagens de Saccharomyces cerevisiae com e sem transportador de sacarose e diferentes atividades de invertase / Sugar metabolization of Saccharomyces cerevisiae with transporter of sucrose and different invertase activity

Parazzi Júnior, Osmar 22 September 2006 (has links)
O presente trabalho teve por objetivo avaliar o perfil metabólico da utilização dos açúcares por diferentes leveduras (BG-1, CAT-1, FLEISCHMANN, PE-2, 1403-7A e LCM001) em diferentes meios de crescimento e também analisar o comportamento e a atividade de invertase destas leveduras durante um processo fermentativo com reciclos de células, semelhantemente ao processo industrial, levando em consideração os parâmetros: produção de etanol, formação de biomassa, produção de trealose, glicogênio, glicerol, rendimento e eficiência fermentativa. Os experimentos foram divididos em três partes: a 1a foi a quantificação da atividade de invertase das diferentes leveduras, em mosto de fermentação à base de mel e água (13% ART), a 2a analisouse o perfil de metabolização em diferentes meios de crescimento à base de YEP com 2% de açúcares (glicose, sacarose, ou glicose + sacarose), e a 3a foi a realização de uma fermentação alcoólica com 4 reciclos de células, com mosto de mel (13% ART), sendo os três primeiros utilizados para a avaliação do rendimento fermentativo, bem como seus indicadores (trealose, glicogênio, viabilidade, entre outros) e o último, destinado ao perfil de metabolização de açúcares em condições de fermentação. Os resultados mostram que as leveduras possuem diferentes atividades de invertase (BG-1 = 7,34; FLEISCHMANN = 5,75; CAT-1 = 3,76; PE-2 = 2,39 gART.h-1.gbiomassa; 1403-7A e LCM001, não possuem atividade), apresentam diferentes velocidades de hidrólise da sacarose, tanto em meios de crescimento como mostos (BG-1 e FLEISCHMANN = 2 h; CAT-1 = 3h; PE-2 = 4h; 1403-7A = 24 h e LCM001 = >24 h), assim como a velocidade de metabolização dos açúcares presentes nestes. Conclui-se que a atividade de invertase é dependente da linhagem de levedura, assim como a velocidade de metabolização dos açúcares em meios de crescimento e mosto. A análise do perfil de metabolização de açúcares não permite identificar a presença de transportador de sacarose. No geral, as leveduras selecionadas apresentam melhor desempenho fermentativo. Por outro lado, verificou-se que as linhagens com transportador de sacarose apesar da menor produção de álcool, apresentaram uma boa eficiência fermentativa. O maior problema por parte destas últimas, é o alto tempo de fermentação e a baixa taxa de multiplicação, com conseqüente queda na viabilidade celular. / The aim of this work was to evaluate the metabolic profile in the utilization of sugars, using different yeast strains (BG-1, CAT-1, FLEISHMANN, PE-2, 1403-7A and LCM001) with different growth medium and also to analyze behavior and the invertase activities of these yeast strains during fermentative process with recycling, similar to the industrial process. The following parameters were used: ethanol production, biomass formation, trealose production, glycogen, glycerol, ethanol yield and fermentation efficiency. The trials were divided into three parts: First was activity quantification of invertase using different yeast strains, with a mix of molasses and water (13% ART), the second was analyzed the metabolization profile with different growth medium using YEP added 2% of sugars (glucose, sucrose, or glucose + sucrose), and the third it was the alcoholic fermentation with 4 yeast cell recycles, using wort of molasses and juice ( 13 % ART), The first three were utilized to evaluate the fermentation yield and also theirs indicatives (trealose, glycogen, viability within others) and, the last one was performed to study the profile of sugars metabolization in fermentation conditions. The results showed that those yeasts produced different invertase activities (BG-1 = 7,34; FLEISCHMANN = 5,75; CAT-1 = 3,76; PE-2 = 2,39 gART.h-1.gbiomass; 1403-7A and LCM001 did not have invertase activity), different velocity of sucrose hydrolysis, as much as medium growth as worts (BG-1 and FLEISCHANN = 2 h; CAT-1 = 3h; PE-2 = 4h; 1403-7A = 24 h and LCM001 = >24 h), also as the velocity of sugars metabolization present on this medium. It can be concluded that the invertase activity is dependent of yeast strain, as the velocity of sugars metabolization in growth medium and wort. The profile analysis of metabolization of sugars did not allow to identify the presence of sucrose transporter. In general, the selected yeasts present the best fermentation performance. On the other hand, it was observed the strains with sucrose transportation did not show stress. The major problem of these yeasts were the high fermentation time and low propagation rate, and a decrease of the viability.
268

The functional consequences of the glucose transporter type 1 gene variations.

January 2006 (has links)
Tsang Po Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 135-152). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Abstract 摘要 --- p.iv / List of Figures --- p.vi / List of Tables --- p.viii / List of Abbreviations --- p.ix / Table of Contents --- p.xii / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter 1.1 --- The Role of Glucose in Biological System --- p.1 / Chapter 1.2 --- Glucose Transporter Families --- p.1 / Chapter 1.2.1 --- Na+-Dependent Glucose Transporters --- p.2 / Chapter 1.2.2 --- Facilitative Glucose Transporters --- p.3 / Chapter 1.3 --- Glucose Transporter Type1 --- p.7 / Chapter 1.3.1 --- Primary Structure of the Glutl Protein --- p.7 / Chapter 1.3.2 --- Secondary Structure --- p.8 / Chapter 1.3.3 --- Tertiary Structure --- p.8 / Chapter 1.3.4 --- Kinetics Properties --- p.11 / Chapter 1.3.5 --- Tissue Distribution --- p.12 / Chapter 1.3.6 --- Multifunctional Property --- p.13 / Chapter 1.3.7 --- Characterization of GLUT1 Gene --- p.13 / Chapter 1.3.8 --- Regulation of GLUT1 Expression --- p.14 / Chapter 1.4 --- Glucose Transporter Type 1 and the Brain --- p.16 / Chapter 1.5 --- Glucose Transporter Type 1 Deficiency Syndrome (GIutlDS) --- p.19 / Chapter 1.5.1 --- Backgronnd of GIutlDS --- p.19 / Chapter 1.5.2 --- Clinical Features of GIutlDS --- p.23 / Chapter 1.5.3 --- Genotype-Phenotype Correlations --- p.24 / Chapter 1.5.4 --- Diagnosis --- p.26 / Chapter 1.5.5 --- Manage nent --- p.27 / Chapter 1.5.5.1 --- Ketogenic Diet --- p.27 / Chapter 1.6 --- Hypothesis and Objectives --- p.29 / Chapter Chapter 2: --- Biochemical and Molecular Analysis of GLUT1 in a Suspected GlutlDS Case --- p.31 / Chapter 2.1 --- Materials --- p.32 / Chapter 2.1.1 --- Clinical History of Suspected GlutlDS Patient --- p.32 / Chapter 2.1.2 --- Blood Samples --- p.32 / Chapter 2.1.3 --- Reagents and Buffers for Reverse Transcription --- p.32 / Chapter 2.1.4 --- Reagents and Buffers for TA Cloning --- p.34 / Chapter 2.1.5 --- Reagents for Genomic DNA Extraction --- p.34 / Chapter 2.1.6 --- Reagents and Buffers for Polymerase Chain Reaction (PCR) --- p.34 / Chapter 2.1.7 --- Reagents and Buffers for Agarose Gel Electrophoresis --- p.35 / Chapter 2.1.8 --- Reagents for Zero-trans 3-OMG Influx in Erythrocytes --- p.37 / Chapter 2.1.9 --- Reagents for Zero-trans 3-OMG Efflux from Erythrocytes --- p.38 / Chapter 2.1.10 --- Reagents for Erythrocytes Membrane Extraction and Detection --- p.39 / Chapter 2.2 --- Methods --- p.44 / Chapter 2.2.1 --- GLUT1 Gene Analysis --- p.44 / Chapter 2.2.2 --- Zero-trans 3-OMG Influx into Erythrocytes --- p.51 / Chapter 2.2.3 --- Zero-trans 3-OMG Efflux from Erythrocytes --- p.52 / Chapter 2.2.4 --- Glutl Protein Expression --- p.54 / Chapter 2.2.5 --- Statistics --- p.57 / Chapter 2.3 --- Results --- p.58 / Chapter 2.3.1 --- Molecular Analysis of the GLUT1 Gene of a Suspected GlutlDS Patient --- p.58 / Chapter 2.3.2 --- Functional Analysis of the GlutlDS Patient's Glutl Protein --- p.61 / Chapter 2.3.3 --- Glutl Protein Expression in the GlutlDS Patient --- p.64 / Chapter 2.4 --- Discussion --- p.66 / Chapter Chapter 3: --- Pathogenicity Studies of GLUT1 Mutations --- p.71 / Chapter 3.1 --- Materials --- p.72 / Chapter 3.1.1 --- Construction of Glutl-Encoding Vectors --- p.72 / Chapter 3.1.2 --- Cell Lire --- p.73 / Chapter 3.1.3 --- "Cell Culture Media, Buffers and Other Reagents" --- p.73 / Chapter 3.1.4 --- Cell Culture Wares --- p.75 / Chapter 3.1.5 --- Reagents for Transfection --- p.75 / Chapter 3.1.6 --- Reagents for Protein Determination and Western Blot Analysis --- p.76 / Chapter 3.1.7 --- Consumables for Confocal Microscopy --- p.77 / Chapter 3.1.8 --- Reagents and Buffers for Flow Cytometry --- p.77 / Chapter 3.1.9 --- Reagents for 2-DOG Uptake in CHO-K1 Cells --- p.77 / Chapter 3.2 --- Methods --- p.79 / Chapter 3.2.1 --- Cell Culture Methodology --- p.79 / Chapter 3.2.2 --- Construction of GLUT1 Mutants --- p.80 / Chapter 3.2.3 --- Establishment of Wild Type and Mutant Glutl Expressing Cell Lines --- p.84 / Chapter 3.2.4 --- Protein Expression Study --- p.85 / Chapter 3.2.5 --- 2-DOG Influx Assay in CHO-K1 Cells --- p.87 / Chapter 3.2.6 --- Confocal Microscopy Studies on Glutl Cellular Localization --- p.89 / Chapter 3.2.7 --- Statistics --- p.90 / Chapter 3.3 --- Results --- p.91 / Chapter 3.3.1 --- Molecular Analysis of 1034-1035Insl2 Mutation --- p.91 / Chapter 3.3.2 --- Expression of the Wild Type and Mutant GFP-Glutl Fusion Proteins --- p.92 / Chapter 3.3.3 --- Functional Analysis of the 1034-1035Insl2 Mutant --- p.95 / Chapter 3.4 --- Discussion --- p.97 / Chapter Chapter 4: --- GLUT1 Promoter Study --- p.100 / Chapter 4.1 --- Materials --- p.101 / Chapter 4.1.1 --- Construction of GLUT1 Promoter Vectors --- p.101 / Chapter 4.1.2 --- Cell Lines --- p.102 / Chapter 4.1.3 --- Cell Culture Media and Other Reagents --- p.103 / Chapter 4.1.4 --- Dual Luciferase Reporter Assay System --- p.103 / Chapter 4.2 --- Methods --- p.105 / Chapter 4.2.1 --- Bioinformatics --- p.105 / Chapter 4.2.2 --- Cell Culture --- p.105 / Chapter 4.2.3 --- Construetion of GLUT1 Promoter Vectors --- p.105 / Chapter 4.2.4 --- 5'-Deletion Analysis of GLUT1 Promoter --- p.108 / Chapter 4.2.5 --- Determination of the Activities of GLUT1 Promoter Fragments --- p.110 / Chapter 4.2.6 --- Statistics --- p.113 / Chapter 4.3 --- Results --- p.114 / Chapter 4.3.1 --- Determination of the Promoter Activity of the 5'-deletion Fragments --- p.114 / Chapter 4.3.2 --- Prediction of Transcription Factors in the 5'-deletion Fragments --- p.119 / Chapter 4.4 --- Discussion --- p.121 / Chapter Chapter 5: --- General Conclusion and Future Perspectives --- p.133 / References --- p.135
269

Investigating the properties of the ZIP4 M3M4 domain in the presence and absence of zinc

Nguyen, Tuong-Vi T 28 April 2011 (has links)
Zinc is the second most abundant transition metal in biological systems. This cation is required for the catalytic activity of hundreds of enzymes which mediate protein synthesis, DNA replication and cell division. Despite the central importance of zinc in cellular homeostasis, the mechanism of zinc uptake, compartmentalization and efflux is unknown. Recently, a family of proteins, called ZIP, has been shown to control zinc uptake. Mutations in one of the genes coding for these proteins (ZIP4) can lead to potentially life-threatening diseases like Acrodermatitis Enteropathica and high levels of ZIP4 have been detected in patients suffering from pancreatic cancer. Therefore our goal is to investigate the mechanism of ZIP4 transport and regulation. It was previously shown that the intracellular loop between transmembrane III and IV (M3M4) of ZIP4 is ubiquitinated in the presence of high intracellular zinc which lead to protein degradation. Our initial hypothesis was that the large intracellular domain of ZIP4 (M3M4) is a sensor which detects the intracellular concentration of zinc and regulates the surface expression of ZIP4. In order to test this hypothesis we expressed and purified the M3M4 domain to examine the ability of M3M4 to bind zinc. Our results have demonstrated that M3M4 binds zinc with a 2:1 zinc:protein stoichiometry with nanomolar affinity. We have also shown that upon binding of zinc, M3M4 undergoes a large conformational change.
270

Effektivisering av intern logistik : Vargön Alloys AB / Rationalisation of internal logistics : Vargön Alloys AB

Berlin, Hanna, Herlogsson, Emma January 2009 (has links)
Med väl fungerande interna logistiska flöden kan hela produktionen effektiviseras samtidigt som man kan skapa mer bränsleeffektiva transporter. Ett företag som är intresserade av att både kunna arbeta mer effektivt med sina transporter och spara på bränsle både för miljön och för kostnadernas skull är Vargön Alloys AB i Vargön utanför Vänersborg.Vargön Alloys är en av Europas största tillverkare av olika Ferrolegeringar. Legeringar ger bl.a. stålet hårdhet och förhindrar korrosion. Företagets kunder är Europas ledande tillverkare av specialstål.Ett problem för Vargön Alloys har varit att man inte har någon dokumentation eller kartläggning över hur de interna transporterna sker idag. Syftet med detta examensarbete är därför att kartlägga hur Vargön Alloys interna transporter sker idag samt att ge förslag till effektivisering, både vad gäller arbetsmetoder och lagerplanering, som leder till minskad bränsleförbrukning samt mindre trafik på fabriksområdet.En kvalitativ undersökningsmetod har använts där observationer följts av intervjuer med personer med olika arbetsområden på företaget. Intervjuobjekten har till största del fått vara anonyma och intervjuerna har skett individuellt med öppna frågor. Användbara teorier studerades i lämpliga läroböcker.Observationer och intervjuer har resulterat i en värdefödeskarta över informationsflödena samt en spagettikarta över transportflödena. Efter analys av dessa har ett antal förbättringsförlag framkommit. Genom att använda nya moderna tekniker som hjälpmedel i arbetet skulle Vargön Alloys definitivt kunna effektivisera sina interna transporter till att bli mer bränsleeffektiva. Med hjälp av ett verktyg som t. ex. GPS timber skulle förtaget få ett system som innehåller både planeringssystem, lagerstyrning och ett GPS-system i fordonen.

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