Tesi sul tema "Molecular aspects"
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1
Shellcock, Carole. "Molecular aspects of algal biofuels". Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=217886.
Testo completoAbstract (sommario):
The ability of micro–algae to respond to diverse and often rapidly changing habitats has been attributed to the versatility of their cellular lipids. Amongst these the energy rich triacylglycerols (TAG) have attracted considerable attention due to their potential use as feedstock for renewable biofuel. Although micro-algae have considerable advantages over other biofuel sources there are constraints to their utilisation. Improvements are required in certain areas including efficiencies in production and enhanced lipid yields if micro-algal biofuels are to become commercially feasible. To achieve this, genetic and metabolic manipulation will be essential and therefore a greater understanding of the lipid biosynthetic pathways is required. In this study the expression of genes putatively involved in TAG biosynthesis in the diatom Phaeodactylum tricornutum was investigated, for the first time, with CO2 supplementation and low pH stress over the entire growth cycle. This molecular analysis was combined with physiochemical examination of the lipid accumulation in the micro-algal model. The results indicated that TAG accumulation was enhanced by CO2 supplementation and occurred predominantly during the stationary growth phase. The molecular analysis revealed increased expression for three genes of interest, encoding enzymes involved in the acyl dependent pathway: Glycerol-3-phosphate acyl transferase (GPAT) -7198728 (Phatrdraft_50031), lysophosphatidic acyl transferase (LPAAT) -7196550 (Phatrdraft_42446) and phosphotidic acid phosphatase (PAP) -7195747 (Phatrdraft_40261) in cultures supplemented with CO2. Under the same conditions up-regulation of a gene involved in the first committed step of fatty acid biosynthesis, Acetyl CoA carboxylase (ACC) -7194806 (Phatrdraft_54926) was also observed. Overall, this study provides further insight on the specific genes linked with increased TAG production in P. tricornutum and the identification of references genes suitable for normalisation of qPCR data across the growth cycle and under CO2 supplementation, thus providing the tools needed for future molecular studies of P. tricornutum lipid production.
2
VanEngelen, Michael Robert. "Molecular aspects of uranium toxicity". Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/vanengelen/VanEngelenM1209.pdf.
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Rakowski, Andrew George. "Molecular aspects of viroid activities /". Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phr162.pdf.
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4
Chauthaiwale, V. M. "Molecular aspects of chainia sp". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1992. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3005.
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Gonçalves, Luiz Ricardo. "Detecção e caracterização molecular de espécies de Mycoplasma e Bartonella em roedores silvestres e sinantrópicos no Brasil /". Jaboticabal, 2016. http://hdl.handle.net/11449/141958.
Testo completoAbstract (sommario):
Orientador: Marcos Rogério AndréCoorientador: Rosangela Zacarias Machado
Banca: Paulo Eduardo Neves Ferreira Velho
Banca: José Maurício Barbanti Duarte
Resumo: Patógenos transmitidos por vetores artrópodes são mundialmente importantes, podendo causar enfermidades tanto no homen quanto nos animais. Recentemente, diversos estudos têm sido realizados a fim de elucidar o papel dos animais selvagens na epidemiologia desses patógenos. A identificação desses microrganismos, assim como dos seus vetores e hospedeiros, permite mapear áreas de ocorrência desses patógenos, auxiliando os órgãos competentes na elaboração de medidas de controle. Sendo assim, o presente estudo teve como objetivo detectar e caracterizar, por métodos moleculares, micoplasmas hemotróficos e bartonelas em amostras de baço de roedores selvagens e sinantrópicos distribuídos em cinco biomas brasileiros. Para tal, foram analisadas 500 amostras de roedores pertencentes a 51 espécies distribuídas em 13 estados. Dentre as 457 amostras de DNA positivas nos ensaios de PCR baseados nos genes Interphotoreceptor retinoid binding protein [IRBP] ou Glyceraldehyde-3-phosphate dehydrogenase [GAPDH], 100 (21,9%) mostraram-se positivas para Mycoplasma spp. por meio da cPCR baseada no gene 16S rRNA. A análise filogenética de 24 sequências do gene 16S rRNA mostrou a presença de dez diferentes clusters, todos agrupados dentro do grupo Mycoplasma haemofelis. O posicionamento filogenético associado com a baixa porcentagem de identidade entre as sequências amplificadas no presente estudo e aquelas previamente depositadas no Genbank sugere a circulação de novas espécies de hemoplasmas em roedo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Arthropod-borne pathogens are wordwide important, causing diseases in humans and animals. Recently, several studies have been performed in order to elucidate the role of wild animals in the epidemiology of these pathogens. The identification of these microorganisms, as well as their vectors and hosts, allow to map the areas of occurrence of these pathogens, helping competent agencies in the development of control measures. Therefore, the present study aimed to detect and characterize, using molecular methods, hemotrophic mycoplasmas and Bartonella in wild and sinantropic rodent spleen samples distributed in five Brazilian biomes. For this purpose, 500 rodent samples belonging to 51 species distributed in 13 states were analyzed. Among 457 DNA samples positive to PCR assays based on the Interphotoreceptor retinoid binding protein [IRBP] or Glyceraldehyde-3-phosphate dehydrogenase [GAPDH]) genes, 100 (21.9%) were positive to Mycoplasma spp. by cPCR based on 16S rRNA gene. The phylogenetic analysis of 24 sequences of the 16S rRNA gene showed the presence of ten different clusters, which grouped within the Mycoplasma haemofelis group. The phylogenetic position associated with the low percentage of identity between the sequences amplified in the present study and those previously deposited in Genbank suggest the circulation of new hemoplasmas species in rodents in Brazil. Additionally, 117 (25.6%) samples were positive to Bartonella sp. by qPCR. The diversity analysis of the gltA ... (Complete abstract click electronic access below)
Mestre
6
Sörgjerd, Karin. "Molecular Aspects of Transthyretin Amyloid Disease". Doctoral thesis, Linköpings universitet, Biokemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12566.
Testo completoAbstract (sommario):
This thesis was made to get a deeper understanding of how chaperones interact with unstable, aggregation prone, misfolded proteins involved in human disease. Over the last two decades, there has been much focus on misfolding diseases within the fields of biochemistry and molecular biotechnology research. It has become obvious that proteins that misfold (as a consequence of a mutation or outer factors), are the cause of many diseases. Molecular chaperones are proteins that have been defined as agents that help other proteins to fold correctly and to prevent aggregation. Their role in the misfolding disease process has been the subject for this thesis. Transthyretin (TTR) is a protein found in human plasma and in cerebrospinal fluid. It works as a transport protein, transporting thyroxin and holo-retinol binding protein. The structure of TTR consists of four identical subunits connected through hydrogen bonds and hydrophobic interactions. Over 100 point mutations in the TTR gene are associated with amyloidosis often involving peripheral neurodegeneration (familial amyloidotic polyneuropathy (FAP)). Amyloidosis represents a group of diseases leading to extra cellular deposition of fibrillar protein known as amyloid. We used human SH-SY5Y neuroblastoma cells as a model for neurodegeneration. Various conformers of TTR were incubated with the cells for different amounts of time. The experiments showed that early prefibrillar oligomers of TTR induced apoptosis when neuroblastoma cells were exposed to these species whereas mature fibrils were not cytotoxic. We also found increased expression of the molecular chaperone BiP in cells challenged with TTR oligomers. Point mutations destabilize TTR and result in monomers that are unstable and prone to aggregate. TTR D18G is naturally occurring and the most destabilized TTR mutant found to date. It leads to central nervous system (CNS) amyloidosis. The CNS phenotype is rare for TTR amyloid disease. Most proteins associated with amyloid disease are secreted proteins and secreted proteins must pass the quality control check within the endoplasmic reticulum (ER). BiP is a Hsp70 molecular chaperone situated in the ER. BiP is one of the most important components of the quality control system in the cell. We have used TTR D18G as a model for understanding how an extremely aggregation prone protein is handled by BiP. We have shown that BiP can selectively capture TTR D18G during co-expression in both E. coli and during over expression in human 293T cells and collects the mutant in oligomeric states. We have also shown that degradation of TTR D18G in human 293T cells occurs slower in presence of BiP, that BiP is present in amyloid deposition in human brain and mitigates cytotoxicity of TTR D18G oligomers.Denna avhandling handlar om proteiner. Särskilt de som inte fungerar som de ska utan har blivit vad man kallar ”felveckade”. Anledningen till att proteiner veckas fel beror ofta (men inte alltid) på mutationer i arvsmassan. Felveckade proteiner kan leda till sjukdomar hos människor och djur (man brukar tala om amyloidsjukdomar), ofta av neurologisk karaktär. Exempel på amyloidsjukdomar är polyneuropati, där perifera nervsystemet är drabbat, vilket leder till begränsad rörelseförmåga och senare till förlamning; och Alzheimer´s sjukdom, där centrala nervsystemet är drabbat och leder till begränsad tankeförmåga och minnesförluster. Studierna som presenteras i denna avhandling har gått ut på att få en bättre förståelse för hur felveckade proteiner interagerar med det som vi har naturligt i cellerna och som fungerar som skyddande, hjälpande proteiner, så kallade chaperoner. Transtyretin (TTR) är ett protein som cirkulerar i blodet och transporterar tyroxin (som är ett hormon som bland annat har betydelse för ämnesomsättningen) samt retinol-bindande protein (vitamin A). I TTR genen har man funnit över 100 punktmutationer, vilka har kopplats samman med amyloidsjukdomar, bland annat ”Skellefteåsjukan”. Mutationer i TTR genen leder ofta till att proteinet blir instabilt vilket leder till upplösning av TTR tetrameren till monomerer. Dessa monomerer kan därefter sammanfogas på nytt men denna gång på ett sätt som är farligt för organismen. I denna avhandling har fokus legat på en mutation som kallas TTR D18G, vilken har identifierats i olika delar av världen och leder till en dödlig form av amyloidos i centrala nervsystemet. Det chaperon som vi har studerat benämns BiP och är beläget i en cellkomponent som kallas för det endoplasmatiska retiklet (ER). I ER finns cellens kontrollsystem i vilket det ses till att felveckade proteiner inte släpps ut utan istället bryts ned. Denna avhandling har visat att BiP kan fånga upp TTR D18G inuti celler och där samla mutanten i lösliga partiklar som i detta fall är ofarliga för cellen. Avhandligen har också visat att nedbrytningen av TTR D18G sker mycket långsammare när BiP finns i riklig mängd.
7
Broomand, Amir. "Molecular aspects on voltage-sensor movement". Doctoral thesis, Linköping : Univ, 2007. http://www.bibl.liu.se/liupubl/disp/disp2007/med1028s.pdf.
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Njålsson, Runa Viđarr. "Molecular aspects of glutathione synthetase deficiency /". Stockholm, 2004. http://diss.kib.ki.se/2003/91-7349-808-4.
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Fawcett, Jonathan. "Molecular aspects of angiogenesis and metastasis". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386753.
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Watkins, Craig Allen. "Molecular aspects of punta toro virus". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239272.
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Amako, Katsumi. "MOLECULAR ASPECTS OF ASCORBATE PEROXIDASE ISOZYMES". Kyoto University, 1997. http://hdl.handle.net/2433/202393.
Testo completoAbstract (sommario):
Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第6912号
農博第930号
新制||農||741(附属図書館)
学位論文||H9||N3036(農学部図書室)
16029
UT51-97-H296
京都大学大学院農学研究科農芸化学専攻
(主査)教授 淺田 浩二, 教授 池田 篤治, 教授 佐藤 文彦
学位規則第4条第1項該当
12
Ballana, Guix Ester. "Molecular basis of deafness linked to mitochondrial DNA mutations". Doctoral thesis, Universitat Pompeu Fabra, 2007. http://hdl.handle.net/10803/7113.
Testo completoAbstract (sommario):
La seqüenciació del genoma humà ha marcat una fita important en la història de la biologia. Com a conseqüència, la genètica i la genòmica han experimentat un progrés enorme. Això ha permès un millor coneixement tant de les causes genètiques de malalties humanes, com del per què de les diferències comunes entre individus. Com a sistemes complexos que som tots els éssers vius, hem de considerar el paper que tenen les interaccions entre les diferents parts del genoma a l'hora d'especificar el resultat final, és a dir, el fenotip. Igualment, podem dir que el genoma conté un conjunt d'instruccions, però que la forma en què aquestes es porten a terme depèn, també de contingències ambientals i històriques. Per tant, la naturalesa de les instruccions genètiques no és completament determinista en tots els casos, si bé hi ha una sèrie de processos en què sí que es compleix aquesta perfecta relació entre herència i expressió final. Aquesta mateixa situació es presenta amb certes alteracions genètiques i amb el desenvolupament de patologies, la qual cosa facilita enormement el diagnòstic precoç i obre les possibilitats per a la teràpia genètica. Però la gran majoria de fenotips, incloent-hi moltes condicions d'interès per a la medicina, tenen una base complexa, és a dir, no existeix "el gen" que determina el caràcter de forma unívoca, sinó que aquest és el resultat de l'acció simultània de molts gens, no tots amb la mateixa participació, juntament amb l'efecte de l'ambient. Aquesta tesi doctoral va arrencar en aquest punt, tenint com a objectiu l'aprofundiment en les bases genètiques d'un tipus de sordesa lligada a mutacions al vi Preface DNA mitocondrial i de la qual se'n tenien evidències de la implicació tant de factors ambientals com diversos factors genètics. D'altra banda, els tests basats en l'ADN són un dels primers usos comercials i d'aplicació mèdica d'aquests nous descobriments de la genètica. Aquests tests poden ser utilitzats per al diagnòstic de malalties, confirmació diagnòstica, informació del pronòstic, així com del curs de la malaltia, confirmar la presència de malaltia en pacients assimptomàtics i amb diferents graus de certesa, predir el risc de futures malalties en persones sanes i en la seva descendència. Aquest és l'objectiu final, i sovint encara utòpic, de la recerca en biomedicina: una millor comprensió del procés biològic, que derivi en un millor tractament i prevenció de la malaltia. Aquesta tesi també ha volgut contribuir humilment en aquest aspecte. Durant aquests anys s'han recollit centenars de mostres de famílies sordes, amb la finalitat de donar un "diagnòstic" de la causa genètica. Poques vegades ho hem conseguit, però en qualsevol cas, si això alguna vegada ha ajudat a algú d'alguna manera, ja em dono per satisfeta.
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Leida, Carmen Alice. "Molecular aspects of dormancy in peach (Prunus persica [L.] Batsch.)". Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/15864.
Testo completoAbstract (sommario):
Dormancy is one of the most important adaptive mechanisms developed by perennial plants, in order to survive the low temperatures of autumn and winter in temperate climates. The study of the genes regulated during dormancy release is crucial to understand the process, with the final objective of the development of new varieties with a better adaptation to certain environments; in particular in the Mediterranean area. The general aim of this work is to understand the molecular and physiological mechanisms underlying the maintenance and release of seasonal dormancy in peach. The first part of this work is focused on the identification of peach genes related to dormancy release by suppression subtractive hybridization (SSH) and microarray hybridization. A significant number of genes identified in this work were homologous to ABA and drought related genes from other species. Our data contribute to highlight a prominent role of ABA in dormancy processes and also uncover elements of the ABA and drought regulatory response in peach, as an ABA-INSENSITIVE5 (ABI5) binding protein (AFP)-like, a dehydration-responsive element (DRE)-binding protein (DREB2C)-like, a calcium-binding annexin, and several genes regulated by stress signalling pathways. Other identified genes were also evaluated to assess the chilling requirement of cultivars by analysis of expression showing a very good correlation between the expression pattern of DAM5, together with other transcripts (BD396, DB247, SB280 and PpB63) and the chilling requirements values of five different varieties ('Big Top', 'Catherina', 'Fergold', 'Maruja' and 'Springlady') measured following Utah and Dynamic models. Furthermore, a study of chromatin modifications associated to dormancy release in the DAM6 gene is presented. A ChIP analysis of DAM6 promoter and structural gene revealed chromatin modification events similar to those observed in vernalization of Arabidopsis and cereals.Leida, CA. (2012). Molecular aspects of dormancy in peach (Prunus persica [L.] Batsch.) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/15864
Palancia
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Cuendet, Michel Alain. "Aspects of thermostated and nonautonomous molecular dynamics /". Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16863.
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Laberge, MacDonald Tammy. "Molecular Aspects of Nitrogen Metabolism in Fishes". Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/668.
Testo completoAbstract (sommario):
Molecular aspects of nitrogen metabolism in vertebrates is an interesting area of physiology and evolution to explore due to the different ways in which animals excrete nitrogenous waste as they transition from an aquatic to a terrestrial lifestyle. Two main products of nitrogen metabolism in fishes are ammonia and urea. Ammonia is produced during protein catabolism and build up of ammonia is toxic. Some aquatic vertebrates convert ammonia into a less toxic compound urea via de novo synthesis through the ornithine-urea cycle (O-UC). Five enzymes are involved in the O-UC: carbamoyl phosphate synthetase (CPS), ornithine carbamoyl transferase (OCT), argininosuccinate synthetase (ASS), argininosuccinate lyase (ASL), and arginase (ARG). An accessory enzyme, glutamine synthetase (GS) also participates in the "fish-type" O-UC. Teleosts excrete ammonia passively over their gills into the aquatic environment. The teleost, Opsanus beta, has been shown to increase urea production after 48 hours of crowding. This thesis explored how crowding stress affected nitrogen metabolite levels of ammonia and urea and O-UC gene expression and enzyme activity in O. beta. Lungfishes while in an aquatic environment avoid ammonia toxicity by releasing excess ammonia across their gills, but when stranded on land they produce urea through the O-UC. Urea production via the O-UC has a metabolic cost of at least four ATP molecules. This thesis explored the response of a lungfish, Protopterus annectens, to six days of aerial exposure and re-immersion conditions by measuring concentrations of O-UC mRNA expression and enzyme activity and nitrogen metabolites ammonia and urea. CPS acts as the entry point to the O-UC and based on enzymatic studies, most aquatic vertebrates utilize one isoform of this enzyme (CPSIII) while terrestrial vertebrates utilize a different isoform of this enzyme (CPSI). Lungfishes are a particularly interesting group of air-breathing fishes, not only because of their link to the origins of tetrapods, but also because CPS I may have originated within this group. Both CPS III and CPS I have been enzymatically described within this group. This thesis uses phylogenetics to investigate how CPS nucleotide sequences in lungfishes evolved compared to other vertebrates.
16
Waghorn, Tania Susanne. "Molecular and Ecological Aspects of Heliothis Armigera". Thesis, University of Auckland, 1999. http://hdl.handle.net/2292/522.
Testo completoAbstract (sommario):
The species status and host range of Heliothis armigera was investigated. DNA profiling, mitochondrial DNA sequencing, RAPD's, along with traditional morphological and crossing methods were used to investigate micro, macro and mega-population structuring. Thirty-six new host records were added, of which a number are important common weeds and crops. Mortality due to parasitoids and fungal infections were quantified on many host species. Genetic analysis of the COII and the AT-rich regions of the mitochondrial DNA showed very high levels of variation, as did the DNA profiling using the probes (CA)n and 33.15. The morphological analyses also showed variation, but to a lesser degree and without statistical significance. The variation found at all levels and in all aspects is discussed with respect to caterpillar host-plants and geographical location. All host-plant populations of caterpillars showed very high levels of genetic variability. However, the population of caterpillars found on Sulla (Hedysarium coronarium) was significantly more variable than those found on Lotus and Lucerne when compared using DNA profiling. The sequences obtained from the two mtDNA regions also showed considerable variation, a great percentage of which was uninformative. This variation did not allude to any structuring of caterpillar populations with respect to host-plant or geographical location. H. armigera is genetically a very variable species which does not equate with any population structuring present in the host-plant or geographical populations investigated here. This study has greatly increased the general understanding of this insect, and has elucidated a portion of the genetic makeup, but not helped in the development any new control methods.
17
Lidén, Martin. "Molecular aspects of retinol uptake and activation /". Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-556-9/.
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Henriksson, Mikael. "Molecular aspects of proinsulin C-peptide interactions /". Stockholm : Department of medical biochemistry and biophysics, Karolinska institutet, 2006. http://diss.kib.ki.se/2006/91-7140-754-5/.
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Josephson, Anna. "Spinal cord injury: mechanical and molecular aspects /". Stockholm, 2002. http://diss.kib.ki.se/2002/91-7349-235-3/.
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Fransén, Karin. "Molecular genetic aspects of colorectal cancer development /". Linköping : Univ, 2005. http://www.bibl.liu.se/liupubl/disp/disp2005/med878s.pdf.
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Vaz, Frédéric Maxime. "Molecular and biochemical aspects of carnitine biosynthesis". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/64280.
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Lovat, Laurence Bruce. "Molecular, therapeutic and clinical aspects of amyloidosis". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400220.
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梁杏媚 e Hang-mei Polly Leung. "Cellular and molecular aspects of myelodysplastic syndromes". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31211628.
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Asztalos, SzilaÌrd. "Molecular aspects of resistance to Orobanche species". Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425596.
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Chaudhry, Shazia A. "Molecular aspects of poliovirus pathogenesis and virulence". Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283788.
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Alfirevic, Ana. "Molecular aspects of carbamazepine-induced hypersensitivity reactions". Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421067.
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Sochi, T. "Atomic and molecular aspects of astronomical spectra". Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1369696/.
Testo completoAbstract (sommario):
In the first section of this thesis, we present the atomic part of our investigation. A C2+ atomic target was prepared and used to generate theoretical data required in the investigation of recombination lines that arise from collisions between electrons and ions in thin plasma found in planetary nebulae and other astrophysical objects. The R-matrix method of electron scattering theory was used to describe the C2+ plus electron system. Theoretical data concerning bound and autoionizing states were generated in the intermediate-coupling approximation by R-matrix and Autostructure codes and compared to experimental data. The comparison revealed very good agreement. These theoretical data were then used to generate dielectronic recombination data for C+ which include transition lines, oscillator strengths, radiative transition probabilities, as well as emissivity and dielectronic recombination coefficients. The data were cast in the form of a line list, called SS1, containing 6187 optically-allowed transitions which include many C II lines observed in astronomical spectra. The data were validated by comparison to C+ recombination data obtained from a number of sources in the literature. This line list was used to analyze the spectra from a number of astronomical objects, mainly planetary nebulae, and identify their electron temperature where the observational data were obtained from the literature. The electron temperature investigation was also extended to include free electron energy analysis which uses observational and theoretical data of FF and FB transitions to investigate the long-standing problem of discrepancy between the results of recombination and forbidden lines analysis and its possible connection to the electron distribution (Maxwellian or non-Maxwellian). In the course of this investigation two elaborate methods, one for finding and analyzing resonances (K-matrix method) and the other for analyzing and identifying electron temperature from astronomical spectra (least squares minimization), were employed. A computer program for atomic transition analysis was also developed and used as the main tool for obtaining the line list and analyzing the observational spectra. In the second section of the thesis we present the results of our molecular investigation; the generation of a comprehensive, calculated line list of frequencies and transition probabilities for the singly deuterated isotopologue of H3+, H2D+. The line list, which is the most comprehensive one of its kind in existence, contains over 22 million rotational-vibrational transitions occurring between more than 33 thousand energy levels and covers frequencies up to 18500 cm-1. All energy levels with rotational quantum number, J, up to 20 are considered, making the line list useful for temperatures up to at least 3000 K. About 15% of these levels are fully assigned with approximate rotational and vibrational quantum numbers. The list is calculated using a previously proposed, highly accurate, ab initio model implemented in a high-accuracy computer code based on a two-stage discrete variable representation (DVR) approach. Various consistency checks were carried out to test and validate the results. All these checks confirmed the accuracy of the list. A temperature-dependent partition function, valid over a more extended temperature range than those previously published, and cooling function are presented. Temperature-dependent synthetic spectra for the temperatures T=100, 500, 1000 and 2000 K in the frequency range 0-10000 cm-1 were also generated and presented graphically.
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Matthew, Caroline Zoe. "Biological and molecular aspects of Sodalis glossinidius". Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/29872.
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Rebholz, Wilhelmus Ewald Reinaard. "Molecular phylogenetics and conservation aspects of antelopes". Doctoral thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/26971.
Testo completoAbstract (sommario):
This thesis concerns the molecular phylogenetics of three tribes of the family Bovidae, the Antilopini, Neotragini, and Tragelaphini. None of these tribes have been studied extensively with molecular techniques. The tribe Antilopini is one of the most speciose tribes (it includes 6 genera with 20 species) and the classification of several species of the genus Gazella is not clear. The tribe Neotragini is thought to be paraphyletic. Mitochondrial sequences of the cytochrome c oxidase ill and cytochrome b genes totalling 1083 base pairs have been determined for 52 taxa and used to determine phylogenetic relationships using cladistic and distance methods. Karyological analysis identified polymorphisms in several species (especially in Gazella saudiya and G. subgutturosa). Karyotypes of G. dorcas pelzelni and an XXY karyotype of a G. dorcas individual are shown for the first time. The main conclusions are that the Antilopini and the Tragelaphini are monophyletic and that the tribe Neotragini is paraphyletic. There is a lack of phylogenetic resolution between tribes which is probably due to the rapid radiation of the different tribes about 20 million years ago. The genus Taurotragus in the tribe Tragelaphini is shown to be paraphyletic and it would be appropriate to incorporate these taxa in the genus Tragelaphus. The genus Gazella could be paraphyletic, due to the position of Antilope cervicapra, in which case the genus needs to be split into two genera or renamed as Antilope. It is also argued that the use of the subgenus Trachelocele should be discontinued and that its only species, G. subgutturosa should be included in the subgenus Gazella. G. rufifrons and G. thomsonii may be more appropriately considered as conspecific. Cytogenetic and sequence data reveal that the herd of G. saudiya in Al Areen Wildlife Park is hybridised with G. bennettii and it is argued that it is important to identify unhybridised G. saudiya in other collections, since this species is on the brink of extinction. This case study demonstrates the need to genetically screen individuals which are part of a captive breeding program, especially if they are intended for reintroduction into the wild.
30
Westwater, Caroline. "Molecular aspects of mannosyltransferases in Candida albicans". Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU543392.
Testo completoAbstract (sommario):
It was of interest to clone key genes involved in O-glycosylation with a view to using reverse genetics to establish their function. The Candida homolog of the S. cerevisiae MNT1 gene (Hausler and Robbins, 1992) was cloned by heterologous probing of a genomic DNA library. The CaMNT1 gene was found to be regulated differentially in response to the environment and exhibited a transitory increase in the level of transcription during early germ tube formation. Low stringency Southern analysis of C. albicans genomic DNA identified several CaMNT1 homologs suggesting CaMNT1 is part of a multigene family whose members are presumed to be yeast Golgi mannosyltransferases. In order to demonstrate that specific glycosyl residues were actively involved in the host-fungus interaction, the CaMNT1 gene was disrupted in two strains using the ura-blaster technique. Disruption at the CaMNT1 locus led to a 90% reduction in -1,2-mannosyltransferase activity when -methyl mannoside was used as an acceptor, but had no obvious influence on viability, growth rate, germ tube formation or proteinase production. CaMnt1 appears to be involved in O-glycosylation since the Camnt1 null mutant strain accumulated intracellularly the O-glycosylated enzyme chitinase. Mannosyltransferase-deficient Camnt1 mutants were significantly reduced in their ability to adhere to human buccal epithelial cells in vitro and were attenuated in virulence in systemic models of candidosis. O-linked mannan may therefore be important for direct interactions with epithelial surfaces or for the stabilization and function of cell surface adhesins. The low virulence potential displayed by Camnt1 mutants clearly demonstrates the important role glycosylation plays in the virulence of C. albicans. Given that O-glycosylation differs significantly between yeast and man, this protein modification may constitute a novel target for antifungal agents.
31
Leung, Hang-mei Polly. "Cellular and molecular aspects of myelodysplastic syndromes /". [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13781455.
Testo completo
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Ip, Julian Chung Yan. "Clinical and molecular aspects of adrenal tumourigenesis". Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/13738.
Testo completoAbstract (sommario):
The aims of this thesis were to examine the clinical and molecular aspects of benign and malignant adrenocortical tumours. Initial research focused on correlating KCNJ5 genotype-phenotype correlations in primary aldosteronism. It was noted that 41% patients were found to have somatic mutations in KCNJ5, G151R and L168R. Mutation carriers were predominately female and significantly younger at presentation and were more likely to be cured following surgery. Further work focussed on malignant adrenocortical carcinoma (ACC). Analysis in a cohort of patients showed that advanced age, advanced disease and the lack of preoperative endocrine investigations were poor prognostic factors. There was also a trend for improved resection margins and recurrence-free survival in patients undergoing surgery with higher-volume surgeons, suggesting that management in experienced units may result in improved outcomes. Tissue microarray technology was utilised in order to identify novel protein signatures that would be able to predict clinical outcomes in patients with ACC. A panel of previously overexpressed genes were validated at the tissue level. A novel combination of predictive and prognostic biomarkers was revealed, with over-expression of Ki-67, TOP2A and EZH2 being associated with poorer outcomes whereas over-expression of BARD1 was associated with improved outcomes. The role of microRNA-129 (miR-129) was explored in ACC tumour biology utilising an ACC cell line, a miRNA known to be under-expressed in adrenocortical tumours. It was found that restoration of miR-129 resulted in cell-cycle arrest, heralding a possible tumour-suppressor role for miR-129. Further investigations demonstrated that SOX4 was a potential downstream target of miR-129, the two having been previously described in other malignancies but not in ACC. The findings in this thesis have provided significant contributions to the understanding of both benign and malignant adrenocortical tumours. However, much work is still needed to refine our understanding of adrenal disease and the findings from this body of work provide the basis for ongoing studies.
33
Rodger, Alison. "Molecular aspects of biomolecule structure and function". Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/516.
Testo completoAbstract (sommario):
All biological processes are fundamentally inter-molecular interactions. In order to understand, and hence control, biomolecular structure and function, methods are required that probe biological systems at the molecular level, ideally with those molecules being in their native environment. The research summarized herein has at its core the development and application of ultra violet (UV)-visible spectrophotometric techniquies for this prupose, in particular circular dichrosim (CD) and linear dichrosim (LD) but also absorbance, fluorescence and resonance light scattering. The spectroscopy is complemented by fundamental theoretical work on molecular structure and reactivity that forms the basis for designing molecules to bind to biomolecules for a particular structural or functional effect. A brief summary of the contributions of the listed publications to our understanding of 'Molecular aspects of biololecule structure and function' is given below under five headings: Circular dichroism theory Molecular geometry and reactivity Small molecule-macromolecule interactions: spectroscopic probes of inter-molecular geometries Molecular design for nucleic acid structure and control Spectroscopic probes of biomolecule structure: instrumentation and application In general terms these correspond to successive phases of the research programme, however, all areas have been present since the first publications in 1983 and can be traced weaving through all subsequent activity.
34
Rodger, Alison. "Molecular aspects of biomolecule structure and function". University of Sydney. Chemistry, 2002. http://hdl.handle.net/2123/516.
Testo completoAbstract (sommario):
All biological processes are fundamentally inter-molecular interactions. In order to understand, and hence control, biomolecular structure and function, methods are required that probe biological systems at the molecular level, ideally with those molecules being in their native environment. The research summarized herein has at its core the development and application of ultra violet (UV)-visible spectrophotometric techniquies for this prupose, in particular circular dichrosim (CD) and linear dichrosim (LD) but also absorbance, fluorescence and resonance light scattering. The spectroscopy is complemented by fundamental theoretical work on molecular structure and reactivity that forms the basis for designing molecules to bind to biomolecules for a particular structural or functional effect. A brief summary of the contributions of the listed publications to our understanding of 'Molecular aspects of biololecule structure and function' is given below under five headings: Circular dichroism theory Molecular geometry and reactivity Small molecule-macromolecule interactions: spectroscopic probes of inter-molecular geometries Molecular design for nucleic acid structure and control Spectroscopic probes of biomolecule structure: instrumentation and application In general terms these correspond to successive phases of the research programme, however, all areas have been present since the first publications in 1983 and can be traced weaving through all subsequent activity.
35
Jenkins, Timothy Mark. "Molecular and metabolic aspects of succinate thiokinase". Thesis, University of Bath, 1988. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383299.
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Wolters, Pieter Jacobus. "Molecular aspects of columnar growth in apple". Doctoral thesis, country:NL, 2014. http://hdl.handle.net/10449/26757.
Testo completoAbstract (sommario):
As rich sources of flavonoids, carotenoids, vitamin C, folic acid and dietary fibre, fruits and vegetables can help prevent cardiovascular diseases and cancers (Amine et al. 2002). According to the world health report that was published by the WHO (2002), 2.7 million deaths per year can be attributed to low fruit and vegetable intake. Apple is the most common fruit crop grown in temperate regions (FAOSTAT 2012) and apples are affordable and widely available in most parts of the world. Apple and apple-derived products have been subject of many studies that have linked their intake to a beneficial effect on many diseases (Hyson 2011). Several studies have indicated a positive effect of phenolic compounds, which are
abundantly present in apple, on preventing coronary heart disease and cancer (Hertog et al. 1993; Keli et al. 1996; Gerhauser 2008). The dietary fibres that are present in fruits like apple seem to decrease the risk for developing coronary heart disease, stroke, hypertension, diabetes, obesity and some gastrointestinal diseases (Anderson et al. 2009). Apples have shown to have high anti-oxidant activity and the intake of apple is associated with a reduced risk for heart disease, lung cancer, type 2 diabetes, and asthma (Boyer and Liu 2004), substantiating the beneficial effects of apple consumption on human health
37
CHIRIACO, MARIA. "Molecular and biological aspects of primary immunodeficiency". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/1126.
Testo completoAbstract (sommario):
Le immunodeficienze primitive (PID) costituiscono un gruppo eterogeneo di disordini genetici causati da alterazioni delle varie componenti della risposta immune innata ed adattiva. Più di 120 geni sono stati identificati come responsabili delle oltre 150 differenti forme PID.
L’eterogeneità genetica e del fenotipo clinico, quest’ultimo caratterizzato da un’alta suscettibilità alle infezioni spesso associata a manifestazioni allergiche, linfo-proliferative ed autoimmuni, rende le immunodeficienze un ottimo modello per lo studio dei meccanismi che regolano lo sviluppo e la funzione del sistema immunitario. Questo lavoro ha lo scopo di suggerire un approccio allo studio delle PID attraverso un’attenta valutazione clinica, genetica e molecolare (studio1 e studio2) e di proporre la terapia genica come cura risolutiva nel caso di immunodeficienze dovute ad un definito difetto genico (studio 3).
Studio1: Lo studio di un paziente con disgammaglobulinemia ed una graduale diminuzione dei linfociti B nel sangue periferico, ha rivelato la presenza di una nuova mutazione nel gene Btk che non compromette l’espressione della proteina. Sebbene la storia clinica e di laboratorio, non è totalmente inconsistente con una variante atipica di XLA, non siamo ancora in grado di stabilire se il quadro clinico è dipendente da questa nuova mutazione o dalla combinazione di più mutazioni che interessano geni diversi.
Studio2: Descriviamo per la prima volta un caso di paziente femmina con immunodeficienza combinata caratterizzata dalla completa assenza delle cellule B, NK e dei loro progenitori ematopoietici. Sorprendentemente la paziente non ha monociti (CD14+) e cellule dendritiche. L’analisi di sequenza dei geni Flt3R e Flt3L e dei geni che principalmente regolano la loro espressione (Ikaros e PU.1), non ha evidenziato alcuna mutazione. I livelli di Flt3R mRNA e Flt3R mRNA nel sangue periferico risultano significativamente più alti (10- e 30- volte aumentati rispettivamente) rispetto al controllo sano, supportando così la nostra ipotesi di uno sbilanciamento dell’espressione dell’mRNA dell’Flt3 ligand. Questi risultati considerati alla luce di uno stroma funzionale nella nostra paziente, potrebbero suggerire il trapianto come strategia terapeutica futura.
Studio3: La terapia genica potrebbe rappresentare la cura definitiva di pazienti per i quali non è possibile fare il trapianto di midollo. Sin dal 997, diversi trial clinici per la terapia genica della XCGD sono stati proposti, ma non sono mai risultati efficaci per una cura a lungo termine. In questo studio noi sviluppiamo una nuova strategia per la terapia genica in pazienti XCGD, basata sui vettori lentivirali e la nuova tecnologia dei microRNA per un controllo del transgene ad un livello post-trascrizionale.Background: Primary immunodeficiency diseases (PIDs) comprise a genetically heterogeneous group of disorders which affect distinct components of the innate and adaptive immune system. Over 120 distinct genes have been identified, whose abnormalities account for more than 150 different forms of PID. Clinical presentation is highly variable; actually ranging from various patterns of microbial susceptibility to allergy, lymphoproliferation or autoimmune manifestations. The study of patients affected by immunodeficiencies allows to identify new genes involved in the immune response indeed PIDs represent an optimal model to investigate development, function and regulation mechanisms of immune system. Aim of the study: To define a rational approach to recognize immune deficiencies, with specific emphasis on developing clinical evaluations, understanding the genetic and cellular basis of the disease (Study1 and Study 2), and propose a gene therapy approach as a definitive cure of immunodeficiency due to a defined genic defect (Study3). study1: We report a patient with dysgammaglobulinemia, and gradual decrease of peripheral B lymphocytes. A new Btk mutation was identified in this patient and protein expression was determined. Although clinical and laboratory history is not totally inconsistent with an atypical variant of XLA, it is unclear if all the clinical presentation/picture is influenced by the new mutation. Study2: We report for the first time a case of a female patient with combined immunodeficiency characterised by a complete absence of B cells and NK cells, and their progenitors. Surprisingly, she had an absence of monocytes (CD14+) and DC cells. Direct sequencing of genomic and cDNA of Flt3L, Flt3R, and of major genes (Ikaros and of PU.1) regulating the FLT3-FLT3L expression did not show the presence of any mutations. Levels of Flt3R and Flt3L mRNA in peripheral blood resulted significantly higher (10- and 30- fold increase respectively) with respect to healthy control donor, supporting the hypothesis of an inherited imbalance in the expression of Flt3 ligand mRNA. This finding, in addition to a normal stromal function highlights the possibility of a more specific therapeutic strategy in this child, such as haematopoietic stem cells transplantation. Study3: Gene therapy could represent a definitive cure for patients for whom conventional HSCT is not available. Several clinical trials on XCGD-gene therapy have been conducted since 1997, but they resulted in low and short-term engraftment of CGD-corrected cells. In this study we develop a new strategy for XCGD gene therapy with stem cells, including Lentiviral Vector (LVV) design and microRNA technology, for a safe and effective treatment of X-CGD.
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Ragazzon, Giulio <1989>. "Operating Molecular Machines: Thermodynamic and Kinetic Aspects". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8043/1/Ragazzon_PhDThesis.pdf.
Testo completoAbstract (sommario):
Artificial Molecular Machines are nowadays an established field of Chemistry, fully recognized by the recent award of the Nobel Prize to Sauvage, Stoddart and Feringa. However, in comparison with their natural counterpart, they can be considered trivial objects. Indeed efforts to improve their functions, their structural complexity and their ability to perform work while exploiting a continuous energy supply are needed, in order to make these unique artificial molecules useful - ultimately - to society. This thesis collects some of the recent work performed in our lab, aimed at tackling these challanges.
39
Rawat, U. B. "Biochemical and molecular aspects of neurospora crassa". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1998. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3385.
Testo completo
40
Tanksale, A. M. "Molecular aspects of a fungal alkaline protease". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2001. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2897.
Testo completo
41
George, S. P. "Molecular and biochemical aspects of extremophilic actinomycete". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2001. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2315.
Testo completo
42
Cheng, Yin-wo, e 鄭燕和. "Molecular basis for the increased osteoblast activity in a mouse modelwith hyperostosis". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B34612981.
Testo completo
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武廣文 e Guangwen Wu. "Molecular simulation studies of platinum and oxygen on a graphite surface". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31236315.
Testo completo
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彭志明 e Chi-ming Pang. "Molecular analysis of the dehalogenase IVa of Burkholderia cepacia MBA4". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31240872.
Testo completo
45
Higaki, Sayuri. "Molecular aspects of brain aging in female macaques". 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157838.
Testo completo
46
Mallon, Patrick William Gerard School of Medicine UNSW. "Clinical and molecular aspects of HIV-associated lipodystrophy". Awarded by:University of New South Wales. School of Medicine, 2006. http://handle.unsw.edu.au/1959.4/33048.
Testo completoAbstract (sommario):
HIV-associated lipodystrophy (HIVLD) syndrome is a condition comprising abnormalities in distribution of body fat and metabolism of lipids and glucose that arises in HIV-infected patients on long-term antiretroviral therapy. This thesis describes clinical research into aspects of the natural history and treatment of HIVLD, as well as molecular research into its pathogenesis centred on subcutaneous adipose tissue. Results demonstrate HIVLD to be a treatment-induced syndrome characterised by initial gains in body fat followed by selective, progressive loss of limb fat. Exposure to thymidineanalogue nucleoside reverse transcriptase inhibitors (tNRTI) induces lipoatrophy through mitochondrial dysfunction of which inhibition of mitochondrial RNA expression, rather than mitochondrial DNA depletion, is an early feature. Mitochondrial dysfunction is associated with decreases in expression of peroxisome proliferatoractivated receptor gamma (PPAR??), an adipocyte transcription factor, which helps explain how tNRTI exposure leads to the loss of adipocyte function. Once established, lipoatrophy is characterised by mitochondrial DNA depletion, although this depletion occurs throughout the mitochondrial genome, suggesting an underlying cause other than inhibition of DNA polymerase gamma. HIVLD is a difficult syndrome to treat. Lipoatrophy is resistant to treatment with rosiglitazone, an agonist of PPAR??, which is ineffective in the setting of ongoing tNRTI therapy and mitochondrial dysfunction. Dyslipidaemia is also difficult to treat as use of pravastatin in the setting of ongoing exposure to protease inhibitors results in only modest declines in fasting cholesterol concentrations. Gains in central fat, such as that seen in patients with buffalo hump, are associated with insulin resistance and diabetes, but only occur in a relatively small percentage of treated patients, suggesting a role for genetic factors in its development. Use of strategies such as avoidance of tNRTI in firstline ART, genetic screening to identify those at risk of toxicities and targeted selection of interventions in subgroups of affected patients, may help prevent this syndrome occurring and better treat those patients in which it has already occurred.
47
Feng, Jianrong. "Molecular and environmental aspects of latex film formation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0008/NQ28278.pdf.
Testo completo
48
Topalović, Tatjana. "Catalytic bleaching of cotton: molecular and macroscopic aspects". Enschede : University of Twente [Host], 2006. http://doc.utwente.nl/57688.
Testo completo
49
Alimov, Andrei. "Molecular genetic aspects of renal cell carcinoma development /". Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-559-X/.
Testo completo
50
Stark, Lisa. "Staphylococcus aureus : aspects of pathogenesis and molecular epidemiology". Doctoral thesis, Linköpings universitet, Institutionen för klinisk och experimentell medicin, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97343.
Testo completoAbstract (sommario):
Staphylococcus aureus is a human commensal colonizing about 30 per cent of the population. Besides, it is a frequent cause of infections such as skin, wound and deep tissue infections and also more life-threatening conditions such as pneumonia, endocarditis and septicaemia. S. aureus may also cause different toxicoses. Moreover, this bacterium is one of the most common causes of nosocomial infections worldwide and an increase in antibiotic resistance, especially against methicillin, is seen. This underlines the importance to prevent and control outbreaks of S. aureus. The aims of this thesis were to increase the knowledge of S. aureus virulence and pathogenesis as well as to understand pattern of colonization and transmission. Various virulence factors operate together in the pathogenic process of S. aureus. The virulence of S. aureus was studied by the interaction with human umbilical vein endothelial cells (HUVEC) as a model. In paper I, we found that one bacterial isolate survived intracellularly and that 156 genes were differentially regulated in microarray analysis of HUVEC. The major part of these genes coded for proteins involved in innate immunity. In paper II, we wanted to explore possible differences in global gene expression patterns in HUVEC induced by invasive compared to colonizing isolates of S. aureus. We also used microarray to investigate possible differences in the presence of virulence genes between the two groups. The main finding was that virulent and commensal S. aureus did not differ in interaction with HUVEC and in the presence of virulence genes. All isolates survived intracellularly for days. Since no obvious differences in virulence between the two groups of isolates were found, we focused on epidemiology and transmission patterns. Colonization with S. aureus is an important risk factor for subsequent S. aureus infection. In paper III, we investigated S. aureus colonization and transmission among nursing home residents in three regions in the south of Sweden and used staphylococcal protein A (spa) typing as an epidemiological tool. A diverse distribution of different spa types was found and a majority of types were unique to one individual. Interestingly, we found a local accumulation of one spa type in one nursing home. Also common spa types were equally distributed in the different regions. We also noted that some individuals were colonized with two different spa types of S. aureus and in five of these cases there was one resistant and one non-resistant strain. The issue of multiclonal colonization and infection is highly important and clinical diagnostic laboratories do not routinely address this problem. Therefore, in paper IV a novel method to assess multiclonality of S. aureus was developed. It was based on denaturing gradient gel electrophoresis with the amplification of the spa gene. The method simultaneously separated eight different spa types. It also detected two spa types in an outbreak. In conclusion, we found no differences in virulence genes and in the interaction with HUVEC between commensal and invasive isolates. This indicates that any isolate of S. aureus might have a pathogenic potential. We also confirmed that some spa types are more successful colonizers with a potential to nosocomial spread. The method for detection of multiclonality of S. aureus is of importance in future epidemiological and clinical studies.