Fímbrias do tipo IV estão associadas a diversos fenótipos em bactérias gram-negativas, e o presente estudo consistiu na caracterização da fímbria Pil e investigação de seu papel na adesão bacteriana de isolados de EPEC atípica. Por PCR e RT-PCR foram investigadas a presença e a funcionalidade do operon Pil e os resultados demonstraram que este está sendo transcrito somente nos isolados BA558 e BA956. Os genes pilS e pilV foram clonados em vetor de expressão para obtenção das proteínas Pil recombinantes e produção de anticorpos policlonais. A análise qualitativa dos testes de inibição da adesão utilizando os soros anti-PilS e anti-PilV juntos demonstraram que o isolado BA558 apresentou mudança de fenótipo de adesão. Esses resultados nos permitem concluir que o operon Pil está funcional em BA558 e BA956, e a expressão da fímbria Pil nessas cepas não está relacionada à formação de biofilme e autoagregação, porém a proteína fimbrial PilS juntamente com a adesina PilV parecem exercer uma função acessória importante na interação de BA558 às células HEp-2. / Type IV fimbriae are associated with several phenotypes in gram-negative bacteria. The aim of this study was the characterization of the Pil fimbria and its role in the interaction of atypical EPEC isolates in bacterial adhesion. Using PCR and RT-PCR, we investigated the presence and functionality of the pil operon genes. The results showed that these genes are transcribed only in the BA558 and BA956 isolates. The pilS and pilV genes were cloned into an expression vector for recombinant proteins and polyclonal antibodies production. Qualitative analysis of the adherence inhibition assays using both rabbit sera changed to localized-like the phenotype of BA558 isolate adhesion. Together, these results allow us to conclude that the Pil operon is functional only in the BA558 and BA956 isolates and that the expression of Pil fimbriae in aEPEC is not related to biofilm formation and autoaggregation but, the fimbrial PilS protein together with PilV adhesin seem to play an important accessory function in the interaction between the BA558 and epithelial cells in vitro.

Ces dernières années, les recherches industrielles et académiques ont connu des bouleversements sans précédents liés à la notion de Développement Durable. Les exigences en matière de santé et d’environnement ont poussé les chimistes à concevoir des produits et procédés chimiques qui permettent de réduire ou d’éliminer les substances dangereuses. Les travaux de recherche décrits dans cette thèse s’inscrivent dans ce contexte et concernent la mise au point de nouveaux systèmes réducteurs utilisant des hydrosiloxanes comme substituts des hydrures d’aluminium et de bore. Dans cet objectif, des systèmes associant le 1,1,3,3-tétraméthyldisiloxane (TMDS) ou le polyméthylhydrosiloxane (PMHS) avec des complexes de titane ou de vanadium ont été développés pour la réduction des fonctions amides et nitriles. La nature de l’association hydrosiloxane – métal et du substrat étudié a joué un rôle important sur la performance et la sélectivité des réactions misent en oeuvre. D’une part, les réductions sélectives d’amides (tertiaires et secondaires) et de nitriles en aldéhydes ont été réalisées respectivement en présence du tétraisopropylate de titane(IV) et du triisopropylate d’oxyde de vanadium(V). D’autre part, les réductions d’amides primaires et de nitriles ont conduit aux amines primaires en présence de tétraisopropylate de titane(IV). Enfin, ces systèmes réducteurs ont été utilisés pour la synthèse d’hétérocycles azotés saturés. La réduction de composés dinitriles donne lieu à une réaction d’alkylation réductrice intramoléculaire qui conduit à la formation de dérivés de la pipéridine, de la pyrrolidine et de l’azétidine en une étape / In recent years, industrial and academic researches have experienced unprecedented changes related to the concept of sustainable development. Health and environment new requirements have prompted chemists to develop chemical products and processes that reduce or eliminate hazardous substances. The research work described in this thesis is focused on the development of new reducing systems using hydrosiloxanes as substitutes for aluminum and boron hydrides. In order to achieve this goal, reducing systems combining 1,1,3,3-tetramethyldisiloxane (TMDS) or polymethylhydrosiloxane (PMHS) with titanium or vanadium complexes have been developed for the reduction of amides and nitriles. The nature of both the association “hydrosiloxane – metal” as well as the studied substrate played an important role on the performance and the selectivity of the reaction. On the one hand, selective reductions of amides (tertiary and secondary) and nitriles to aldehydes were carried out respectively in the presence of titanium(IV) tetraisopropoxide and vanadium(V) triisopropoxide oxide. On the other hand, reductions of amides (primary) and nitriles afforded the corresponding primary amines in the presence of titanium(IV) tetraisopropoxide. Finally, these systems have been applied for the synthesis of saturated N-heterocycles. Reduction of dinitrile compounds led, in one step, to piperidine, pyrrolidine and azetidine derivatives through an intramolecular reductive alkylation reaction

Questo lavoro studia la distribuzione della dimensione d'impresa sulla base di due datasets. Il primo è l'indagine micro1 di istat, che include tutte le imprese manifatturiere con più di 20 addetti sopravvissute dal 1989 al 1997. Il secondo è il file Cerved riguardante l'universo delle imprese del settore meccanico (atecodk29), dal 1997 al 2002. Lo scopo generale della tesi è quello di espolare la possibilità di trovare nuove regolarità empiriche riguardanti la distribuzione della dimensione d'impresa, sulla base della passata evidenza empirica che attesta la (in)capacità di Lognormale e Pareto di modellare in modo soddisfacente la dimensione d'impresa nell'intero arco dimensionale. Vengono per questo proposti due modelli mai utilizzati prima. Gli stessi vengono poi convalidati su differenti variabili dimensionali e a diversi livelli di aggregazione. La tesi cerca anche di esplicitare al meglio le implicazioni economiche dei modelli parametrici di distribuzione adottati secondo diversi punti di vista. / The present work studies the firm size distribution of Italian manufacturing industries on the basis of two datasets. The first is the Micro1 survey carried out by ISTAT, which recorded all manufacturing firms with 20 employees and more surviving from 1989 to 1997. The second is the Cerved file regarding all firms of the mechanical sector (DK29) from 1997 to 2002. The general aim of this research is to explore the possibility to find new empirical regularities in the size distribution of firms, building on the relevant past evidence about the (in) capacity of the Lognormal and Pareto distribution of satisfactorily modelling the whole size range. Two unused statistical models are proposed and validated on different size proxies and at different levels of data aggregation. The thesis also addresses the economic implications of parametric models of firm size distribution in different aspects.

Psykisk hälsa/ohälsa är ett svårdefinierat begrepp som sätter fingret på ett av de största folkhälsoproblemen i vårt land, där depression är en av de vanligaste diagnoserna. Manualerna DSM-IV TR och ICD-10 används inom stora delar av sjukvården, världen över, i syfte att ge kunskap om lämpligast behandling till patienter med psykiska besvär. Denna studie syftar till att, genom en kvalitativ analys, undersöka vilka grunder som finns bakom de vanligast använda diagnosmanualerna och vilka kriterier som krävs för att uppfylla två vanligt förekommande diagnoser, PTSD och svår depression. Vidare syftar studier till att belysa eventuella likheter och olikheter mellan dessa diagnoser och vad det kan föra med sig. Såväl psykologisk forskning som klinisk praktik utgår idag mestadels från psykiatriska diagnoser, vilket kan ha såväl fördelar som nackdelar, men samtidigt diskuteras huruvida man istället ska lägga fokus på en annan mer underliggande nivå, nämligen processerna som sträcker sig över diagnosernas gränser. Fördelarna med ett transdiagnostiskt perspektiv är att det delvis kan ge en förklaring till den höga komorbiditet som finns i kliniska grupper och som skulle kunna iakttas även i de sjukdomsbilder som denna studie fokuserar på. Unified Protocol är en annan behandlingsmodell som tas upp i studien, vilken baseras på en betydande fenotypisk över-lappning mellan olika ångeststörningar hos patienter, där personer med subkliniska nivåer av symtom ändå kan ha en nedsatt funktionsnivå och ett subjektivt lidande, fastän de inte uppfyller alla de diagnostiska kriterierna för en specifik störning. Resultatet visar på möjligheten att se över diagnosgränser, för att öka chanserna för ett tillfrisknande hos patienten. Människans upplevelser av olika situationer den befinner sig i formas av personens egen uppfattning om sin förmåga, eller oförmåga, att påverka resultatet. Att uppleva sig ha mist kontroll över sitt eget liv kan i sig leda till såväl depression som suicidala tankar/-handlingar. Om symtomen för depression jämförs med kriterierna som står att finna under diagnosbilden “Posttraumatiskt stressyndrom” under kapitlet “ångestsyndrom”, kan många likheter konstateras. Slutsatsen blir att likheterna i symtombild skulle ge patienter med PTSD en behandlingsrekommendation som inte alls överensstämmer med de rekommenderade riktlinjer som är utformade för PTSD. Trots diagnosernas likheter rekommenderas olikartad behandling, och även olika förutsättningar för att fungera i kombination med förvärvsarbete påvisas. Vid så lika symtombilder, men ändå så skilda rekommenderade behandlingsplaner utifrån de olika diagnoserna, torde risken för en felaktig rehabiliteringsplan vara över-hängande. / Mental health/illness is complex to define and this highlight of the biggest public health problems in our country, in which depression is one of the most common diagnoses. The manuals DSM-IV TR and ICD-10 is used in much of health care, worldwide, in order to provide knowledge of appropriate treatment for patients with mental disorders. This study aims to, through a qualitative analysis, examine the grounds behind the most commonly used diagnostic manuals and the criteria required to meet two common diagnoses, PTSD and severe depression. Further studies aimed to highlight any similarities and differences between these diagnoses and what it can bring. Both psychological research and clinical practice today is based mostly from psychiatric diagnoses, which can have both advantages and disadvantages, but also discussed whether they should instead focus on another more underlying level, namely the processes that extend across the diagnostic boundaries. The advantages of a trans-diagnostic perspective are that it may partly explain the high co-morbidity found in clinical groups and that could be observed even in those syndromes which this study focuses on. Unified Protocol is a different treatment model that is entered in the study, which is based on a significant phenotypic overlap between anxiety disorders in patients, where individuals with subclinical levels of symptoms still can have a reduced level of functionality and a subjective suffering, although they do not meet all the diagnostic criteria for a specific disorder. The result shows at the opportunity to review the diagnostic boundaries, to increase the chances for a recovery of the patient. The human experiences of different situations it is in the form of personal self-perception of their ability, or inability, to influence the outcome. To experience they have lost control over his own life in itself can lead to both depression that suicidal thoughts / actions. If the symptoms of depression compared with criteria that are to be found during diagnostic image "Post-traumatic stress disorder" in the chapter "disorder" can be found many similarities. The discourse comes to that the similarities in symptoms would provide patients with PTSD, a treatment recommendation, which did not conform to the recommended guidelines that are designed for PTSD. Despite the diagnosis, the similarities are recommended disparate treatment, and also different conditions to work in conjunction with work shown. At this same symptom pictures, yet so different recommended treatment plans based on the different diagnoses, would risk a false rehabilitation plan to be imminent

RAGE (receptor for advanved glycation endproducts) was identified on endothelial cells as binding partner for AGE-modified molecules. The term "Advanced glycation endproducts" involves a number of structurally diverse molecules, which derive from multiple complex rearrangements of reducing sugars with free amino-groups of proteins. They evolve during food production and also in vivo during ageing and to an accelerated degree in diabetes, where AGEs cause receptor-mediated cellular perturbations. Due to the pathological relevance the aim of this thesis was to generate a "biosensor" for AGEs. To this end, the membrane-expressed receptor (flRAGE) as well as soluble RAGE (sRAGE) were expressed in mammalian cells and investigated in numerous binding studies. These did not reveal a specific interaction of AGE-modified ligands with RAGE. In addition, the expression of RAGE on endothelial cells, as described in the literature, could not be followed neither with the help of newly generated monoclonal anti-RAGE antibodies, nor in quantitative "real time" RT-PCR analysis. These results cast doubts on the meaning of RAGE as a proinflammatory receptor in AGE-mediated pathologies and on the adequacy of RAGE for the "biosensor". At the same time the question concerning a physiological role of the receptor arose. RAGE-expression was analysed in different healthy human tissues by "real time" RT-PCR, which revealed an almost selective expression in lung tissue. An important indication for a possible physiological function of RAGE in lung provided the selective localization of RAGE on alveolar epithelial type I cells as demonstrated in frozen lung sections as well as in in vitro cultivated lung cells. RAGE could be identified as a novel, highly specific marker for the thin, expanded AT I cell, which form part of the air-blood-barrier. In the following, RAGE was found to be an interaction partner for collagen IV, a major component of the alveolar basal lamina. Membrane-expressed RAGE did not only strengthened adherence of cells but also induced cell spreading on collagen IV-coated surfaces. This preferential interaction of RAGE with collagen IV could substantially contribute to the functional morphology of AT I cells in vivo, thereby ensuring an effective bidirectional gas-exchange. The results of this thesis expose a novel, so far unnoticed aspect of the biology of RAGE, which presumably contributes to the phenotypic characteristic und function of normal human lung tissue. / RAGE (receptor for advanced glycation endproducts) wurde als Interaktionspartner auf Endothelzellen für AGE-modifizierte Moleküle identifiziert. Unter den "Advanced glycation endproducts" werden eine Vielzahl strukturell unterschiedlicher Moleküle zusammengefasst, die durch mehrstufige komplexe Umlagerungen zwischen reduzierenden Zuckern und freien Aminogruppen von Proteinen entstehen. Sie entstehen sowohl bei der Herstellung von Lebensmitteln, als auch in vivo während des Alterns und in erhöhtem Maß bei Diabetes, wobei sie Rezeptor-vermittelt Zellstörungen hervorrufen. In der vorliegenden Arbeit wurde zunächst aufgrund der pathologischen Relevanz eine Strategie zur Konzeption eines "Biosensors" für AGEs verfolgt. Hierfür wurde sowohl der membranständige Rezeptor (flRAGE) als auch löslicher RAGE (sRAGE) in Säugerzellen exprimiert und in zahlreichen Bindungs- und Funktionsanalysen getestet. Hierbei konnte keine spezifische Interaktion der AGE-modifizierten Moleküle mit RAGE nachgewiesen werden. Auch die in der Literatur beschriebene Expression von RAGE auf Endothelzellen konnte mit Hilfe neu generierter monoklonaler Antikörper, sowie in quantitativen "real time" RT-PCR-Analysen nicht nachvollzogen werden. Diese Ergebnisse warfen Zweifel an der grundlegenden Bedeutung von RAGE als proinflammatorischer Rezeptor in AGE-bedingten Krankheiten auf und stellten damit auch dessen Eignung für einen AGE-Biosensor in Frage. Gleichzeitig warf diese Skepsis die Frage nach einer möglichen physiologischen Funktion dieses Rezeptors auf. Eine vergleichende Analyse der RAGE-Expression in verschiedenen gesunden Geweben mittels "real time" RT-PCR ergab eine nahezu selektive Expression in Lungengewebe. Wichtige Anhaltspunkte für die Funktion von RAGE in der Lunge ergaben sich aus der selektiven Lokalisation des Rezeptors auf Alveolarepithelzellen Typ I (AT I) sowohl in Gefrierschnitten der Lunge als auch nach in vitro-Kultur von Lungenzellen. RAGE konnte als neuer, hoch spezifischer Marker für die lang gestreckten AT 1 Zellen, die einen Teil der Blut-Luft-Schranke bilden, definiert werden. In folgenden Funktionsanalysen konnte RAGE als spezifischer Interaktionspartner für Kollagen IV, einer Hauptkomponente der Alveolar-Basalmembran, identifiziert werden. Membranständiger RAGE verstärkte nicht nur die Adhärenz von Zellen an Kollagen IV-beschichtete Oberflächen, er induzierte auch Zell-"Spreading". Dies gab Anlass für die Vermutung, dass die beobachtete präferentielle Interaktion von RAGE mit Kollagen IV maßgeblich zu der funktionellen Morphologie der AT I Zellen in vivo beitragen könnte, die die Voraussetzung für einen effektiven bidirektionalen Gasaustausch darstellt. Durch die Ergebnisse dieser Arbeit wurde ein neuer, bisher unbeachteter Aspekt der Biologie des RAGE aufgedeckt, der vermutlich entscheidend zur phänotypischen Ausprägung und Funktion des normalen humanen Lungengewebes beiträgt.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present work describes the phytochemical study and biological activity evaluation of the Buddleja brasiliensis Jacq. ex. Spreng and Artemisia verlotorum Lamotte. Were isolated three compounds from Buddleja brasiliensis: verbascoside (1), β-sitosterol (54) and stigmasterol (55), and it was carried out a phytochemical screening, a study of the ability to inhibit the enzymes prolyl oligopeptidase (POP), dipeptidyl peptidase (DPP IV) and acetylcholinesterase (AChE), a study of the antimicrobial activity of the specie and the extraction of the essential oil. The fractions F4 and F12 inhibited significantly POP and AchE activity. All Buddleja brasiliensis fractions tested presented low activity of DPP IV inhibition. The phenylpropanoid verbascoside (1) demonstrated a significant and selective inhibitory activity against POP (IC50 = 1.3 mM), showed weak activity against DPP-IV (IC50 >> 150 mM) and was inactive against AChE (pMIQ 9.6). The essential oil obtained from this species has as major constituents the a-tujaplicin monoterpene (11.5%) and the diterpenoid heneicosane (14.5%). This oil was inactive against all tested enzymes. The antimicrobial activity of 1, the crude extract and fractions of Buddleja brasiliensis were tested against several fungi and bacteria. Fractions dichloromethane and ethyl acetate showed moderate activity against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Streptococcus pyogenes, while 1 showed no antimicrobial activity. The crude extract, fractions and essential oil obtained from Artemisia verlotorum were also evaluated for inhibitory activity against the POP and DPP IV, as well as against various fungi and bacteria. Dichloromethane fraction of Artemisia verlotorum showed the best antimicrobial activity, mainly against the yeast Saccharomyces cerevisiae, with an MIC of 125 μg/mL. Analysis by gas chromatography coupled with mass spectrometry of the essential oil of Artemisia verlotorum indicated as the main components santonilil acetate (37.2%) and a-cadinol (9.59%). / O presente trabalho descreve o estudo fitoquímico e a avaliação da atividade biológica das espécies Buddleja brasiliensis Jacq. ex. Spreng e Artemisia verlotorum Lamotte. De Buddleja brasiliensis foram isolados três compostos: verbascosídeo (1), β-sitosterol (54) e estigmasterol (55). Desta espécie, fez-se a prospecção fitoquímica, a avaliação da capacidade de inibição das enzimas prolil oligopeptidase (POP), dipeptidil peptidase (DPP IV) e acetilcolinesterase (AChE), a obtenção do óleo essencial, e avaliação da atividade antimicrobiana. Nos testes de inibição frente à enzima POP foi observada significativa atividade das frações F4 e F12. Estas frações também demonstraram atividade inibitória da enzima AChE. Nos testes com a DPP IV verificou-se baixa atividade para todas as frações testadas. O fenilpropanóide verbascosídeo (1) demonstrou ter uma significativa e seletiva atividade inibitória frente à POP (IC50 = 1,3 μM), enquanto frente à DPP IV demonstrou fraca atividade inibitória (IC50 >>150 μM) e frente à AChE foi inativo (pMIQ de 9,6). O óleo essencial obtido desta espécie tem como constituintes principais o monoterpeno a-tujaplicina (11,5 %) e o diterpeno heneicosano (14,5 %). Este óleo foi inativo frente a todas as enzimas testadas. A atividade antimicrobiana de 1, do extrato bruto e das frações de Buddleja brasiliensis foi testada frente a vários fungos e bactérias. O composto 1 não apresentou nenhuma atividade antimicrobiana, enquanto que as frações que demonstram atividade moderada foram as frações Diclorometano e Acetato de etila para Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Streptococcus pyogenes. O extrato bruto, as frações e o óleo essencial obtidos de Artemisia verlotorum também foram avaliados quanto a atividade de inibição frente à POP e a DPP IV, bem como frente a vários fungos e bactérias. A fração Diclorometano de Artemisia verlotorum demonstrou a melhor atividade antimicrobiana, principalmente frente ao fungo Saccharomyces cerevisae, com uma CIM de 125 μg/mL. A análise por cromatografia gasosa acoplada a espectrômetro de massa do óleo essencial de Artemisia verlotorum indicou como constituintes principais acetato de santonilila (37,2 %) e a-cadinol (9,59%).

L'objectif de ce travail porte sur la généralisation de la modélisation de la gravure du silicium dans les plasmas de fluor ou de chlore à celle de la gravure des éléments de la colonne IV et des composés III-V de structure cristalline de type diamant ou zinc-blende dans les plasmas d'halogènes, i.e. fluor, chlore, brome et iode. Dans ce contexte, les effets stériques et de diffusion en volume et/ou en surface en constituent les problématiques principales. Cette généralisation s'appuie sur le modèle de gravure de Petit et Pelletier qui, par rapport aux modèles antérieurs, prend en compte un certain nombre d'hypothèses distinctes ou additionnelles telles que les interactions répulsives entre adatomes d'halogènes proches voisins, les mécanismes de Langmuir-Hinshelwood pour la formation des produits de réaction, la nature mono-couche ou multi-couches de l'adsorption, et la diffusion des adatomes en surface. Les effets stériques relatifs à la diffusion des atomes d'halogènes à travers les surfaces (100) des structures cristallines des éléments de la colonne IV et des composés III-V définissent une première loi de similitude entre la maille du réseau cristallin et le rayon ionique de Shannon des atomes d'halogènes concernant leurs conditions de diffusion en volume. Cette loi se traduit par un diagramme prévisionnel, commun aux éléments de la colonne IV et aux composés III-V, délimitant les systèmes de gravure de types mono-couche et multi-couches. Les effets stériques relatifs aux mécanismes réactionnels de gravure sur les surfaces (100) aboutissent à des secondes lois de similitude entre la maille du réseau et le rayon covalent des adatomes d'halogènes caractérisant la nature de la gravure : gravure isotrope, gravure anisotrope, ou absence de gravure. Ces lois de similitude, distinctes pour les éléments de la colonne IV et les composés III-V (stœchiométrie différente des produits de réaction), se traduisent par deux diagrammes prévisionnels délimitant les différents domaines de gravure. Les diagrammes prévisionnels pour les éléments de la colonne IV ont pu être validés, d'une part, à partir des résultats expérimentaux antérieurs, et, d'autre part, en l'absence de données, à partir d'études expérimentales complémentaires : gravure de Si et Ge en plasma de brome et d'iode, gravure de Sn en plasma d'iode. / The objective of this work is the generalization of the modeling of the etching of silicon in fluorine or chlorine plasmas to that of the etching of the elements in column IV and of III-V compounds with diamond-like or zinc-blend crystal structure in halogen plasmas (i.e. fluorine, chlorine, bromine and iodine). In this context, steric effects and volume and/or surface diffusion are the main issues. This generalization is based on the etching model of Petit and Pelletier which, compared to previous models, takes into account a number of separate or additional assumptions such as the repulsive interactions between halogen adatoms in nearest neighbor positions, the Langmuir-Hinshelwood mechanisms for the formation of reaction products, the mono-layer or multi-layer nature of the adsorption, and the diffusion of adatoms on the surface. Steric effects related to the diffusion of halogens through the (100) surfaces of the crystal structures of the elements of column IV and III-V compounds define a first law of similarity between the crystal lattice and the Shannon ionic radius of the halogen atoms concerning their bulk diffusion conditions. This law results in a forecast diagram, common to column IV elements and III-V compounds, delimiting the mono-layer or multi-layer type of the etching systems. Steric effects related to the reaction mechanisms of etching on (100) surfaces lead to the second laws of similarity between the crystal lattice and the covalent radius of halogen adatoms characterizing the etching behavior: isotropic etching, anisotropic etching or no etching. These laws of similarity, distinct between the elements of the column IV and III-V compounds (different stoichiometry of the reaction products), result in two forecast diagrams delimiting the distinct etching domains. Forecast diagrams for column IV elements have been validated, first, from previous experimental results, and, secondly, in the absence of data, from additional experimental studies: etching of Si and Ge in bromine and iodine plasmas, and etching of Sn in iodine plasmas.