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1

Ruyssen, Sylvie. "Structures et synthèses des alcaloi͏̈des des fourmis du genre "Solenopsis"." Paris 5, 1991. http://www.theses.fr/1991PA05P072.

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2

Lebrun, Bruno. "Etude de toxines alcaloi͏̈diquesd'arthropodes : étude physico-chimique et toxicologique du venin des myriapodes du genre Glomeris et analyse électrophysiologique du mécanisme d'action d'un dérivé synthétique d'alcaloi͏̈des présents dans le venin des fourmis du genre Monomorium." Aix-Marseille 1, 1994. http://www.theses.fr/1994AIX11081.

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De precedentes etudes avaient montre que le venin du diplopode glomeris marginata contient deux alcaloides originaux: la glomerine et l'homoglomerine. Nous avons identifie ces alcaloides dans le venin de deux autres especes: g. Annulata et g. Guttata, ainsi qu'un nouveau derive de la quinazolinone, la 6-methoxy-glomerine, dont la structure a ete etablie sur la base de diverses donnees spectrales (uv, rmn-1h, ms). Ces alcaloides sont faiblement toxiques a l'egard des insectes et seules la glomerine et l'homoglomerine ont montre une toxicite significative a l'egard des vertebres (dl50 9. 7 et 6. 4 mg/kg en injection intraperitoneale chez la souris). Les 2,5-dialkylpyrrolidines presentes dans le venin des fourmis du genre monomorium sont des insecticides naturels provoquant une paralysie flasque. Nous avons determine le mecanisme d'action de la 2-(1non-8enyl)-5-(1non-8enyl)pyrrolidine (pyr 9) sur le systeme nerveux d'invertebre, en utilisant deux types de preparations in vitro de la chaine nerveuse ventrale de l'ecrevisse procambarus clarkii). Nos resultats montrent clairement que la pyr 9 bloque la conduction nerveuse sans affecter le potentiel de repos. Des experiences de potentiel impose sur axone ont demontre que ce blocage est du a une inhibition du courant sodium, qui s'accompagne d'un deplacement de la courbe d'inactivation du courant sodium vers les potentiels plus negatifs
3

Radvanyi, François. "Mode d'action possible de la crotoxine, une neurotoxine présynaptique à activité phospholipase A2." Paris 6, 1987. http://www.theses.fr/1987PA066197.

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4

Le, Gall Frédéric. "De la stratégie d'envenimation de Conus consor et de Conus ermineus à la caractérisation biochimique et électrophysiologique de deux toxines de leur venin : des peptides spécifiques des canaux sodium neuronaux." La Rochelle, 1998. http://www.theses.fr/1998LAROS031.

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L'étude de la stratégie d'envenimation utilisée par les trois cônes piscivores c. Catus, c. Ermineus et c. Consor a permis de montrer que ces trois cônes utilisent la stratégie des harpooners qui harponnent leur proie, a l'aide d'une dent radulaire sophistiquée, avant de l'ingérer. Les études élèctrophysiologiques, réalisées sur des préparations nerf-muscle d'amphibien, montrent que les venins de c. Catus, c. Ermineus et c. Consor contiennent (I) des toxines qui agissent au niveau présynoptique en augmentant l'excitabilité des terminaisons nerveuses et (II) des toxines qui agissent au niveau postsynaptique en bloquant les récepteurs nicotiniques de l'acétylcholine. Nous avons entrepris la caractérisation les toxines contenues dans les venins de c. Consor et c. Ermineus qui agissent au niveau présynoptique. Nous avons ainsi isole deux nouvelles conotoxines : la conotoxine-evia a partir du venin de c. Ermineus et la CCTX a partir du venin de c. Consor. L'étude des effets biologiques induits par ces deux toxines a montre qu'elles étaient, du moins en partie, responsables du choc excitotoxique observe lors de l'envenimation d'un poisson par ces cônes. Seule la conotoxine-evia est active chez le mammifère avec une ed50 de 4,1 pmoles/g de souris. Cette toxine est un polypeptide de 32 résidus d'acides amines réticules par trois ponts disulfures. Le mécanisme d'action physiologique de cette toxine a été étudié sur des préparations neuromusculaires et des axones myelinises isolés d'amphibien. L'ensemble des résultats obtenus montre que l'action de la conotoxine evia est d'inhiber l'inactivation des canaux sodium neuronaux sans affecter ceux des muscles squelettiques. Cette action se traduit par une augmentation (I) de la durée du potentiel d'action au niveau des axones et (II) de l'excitabilité membranaire au niveau des terminaisons nerveuses. La CCTX est un polypeptide de 30 résidus d'acides amines et possède une modification post-traductionnelle au niveau du résidu 7. Des études élèctrophysiologiques ont montre que cette toxine active sélectivement les canaux sodium neuronaux au potentiel de repos, ce qui provoque une augmentation de l'excitabilité nerveuse et ce, sans affecter le muscle squelettique. La spécificité d'action de la CCTX et de la conotoxine-evia en font des outils pharmacologiques remarquables pour distinguer les canaux sodiques neuronaux des canaux sodiques musculaires au sein d'une même espèce.
5

Favreau, Philippe. "Etudes physico-chimique et pharmacologique de nouvelles toxines isolées du venin du cône piscivore Conus Consors." La Rochelle, 1999. http://www.theses.fr/1999LAROS034.

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Le venin du cône piscivore conus consors a ete etudie afin d'isoler et de caractériser de nouvelles conotoxines utiles pour l'étude de ces protéines membranaires. Deux alphaconotoxines, l'alpha-cnia et l'alpha-cnib, qui ciblent les récepteurs nicotiniques de l'acetylcholine ont été isolées du venin. La synthèse de l'alpha-cnia a ete realisee par synthese peptidique en phase solide selon la strategie fmoc. Les études de liaison de l'alpha-cnia, a des récepteurs nicotiniques de torpille et alpha 7, ont montre que cette toxine se fixe spécifiquement sur les récepteurs de type musculaire. Enfin, l'élucidation de la structure tridimensionnelle par rmn de l'alpha-cnia a permis de mettre en évidence la présence de différents conformeres en solution ainsi qu'une heterogeneite conformationnelle du conformere majoritaire. Une nouvelle omega-conotoxine, l'omega-cnviia, a été isolée du venin, caractérisée puis obtenue par synthèse peptidique en phase solide selon la méthode fmoc. L'étude de la liaison aux synaptosomes de rat, realisee par radiomarquage a l'iode 125 de l'omega-cnviia, montre que le peptide se lie de façon spécifique et réversible au canaux calcium de type n, avec un k d de 36 pm. Cependant, cette toxine présente un profil pharmacologique différent de l'omega-gvia. L'omega-cnviia représente donc un nouvel outil pharmacologique pour l'étude de canaux calcium de type n. Finalement, trois excitotoxines, les delta-cnvia, cnvib et cnvic, ont été isolées. Elles sont en partie responsables du choc excitotoxique observe lors de l'envenimation de la proie. L'effet biologique de la delta-cnvia a été étudié au niveau de la jonction neuromusculaire et sur des cellules du système nerveux central de vertèbres. L'ensemble des résultats obtenus montre que la delta-cnvia inhibe l'inactivation des canaux sodium sensibles au potentiel de membrane.
6

Maillère, Bernard. "Étude de la présentation aux lymphocytes T murins d'une protéine riche en ponts disulfure : le cas d'une neurotoxine de venin de serpent." Paris, Institut national d'agronomie de Paris Grignon, 1992. http://www.theses.fr/1992INAPA001.

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7

Rifflet, Aline. "Etude toxinologique du venin de fourmis exotiques : identification et caractérisation d’un peptide antimicrobien." Thesis, Montpellier 1, 2012. http://www.theses.fr/2012MON13509/document.

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Les venins animaux, par leur richesse biochimique et la diversité de leurs cibles moléculaires, sont une source importante de molécules dont les applications potentielles sont nombreuses. La recherche de nouveaux médicaments pour remplacer certains antibiotiques devenus inefficaces face à l'apparition de résistances, est un axe fort de la recherche pharmacologique. Depuis plus de 40 ans, la découverte de toxines animales montre que les animaux venimeux peuvent être les « pharmaciens du futur ». Le venin de fourmis est encore peu étudié. Seul celui de quelques espèces a été exploré, avec à chaque fois la mise en évidence de toxines originales. L'objectif de cette thèse a été l'étude du venin de fourmis exotiques sur la base d'une approche pluridisciplinaire qui combine l'analyse biochimique et la toxinologie. Les travaux se sont articulés autour de deux axes principaux : (1) Recherche d'activités biologiques sur insectes et bactéries ; (2) Fractionnement des venins par des techniques séparatives et analyse biochimique des peptides isolés par spectrométrie de masse. Deux espèces de fourmis ont été choisies en fonction de leur mode de vie : Crematogaster striatula, une espèce arboricole et Tetramorium bicarinatum, une espèce terricole. Les différentes activités biologiques de leurs sécrétions venimeuses ont été conduites par test MTT. Le liquide de Dufour de C. striatula en plus de sa capacité à éloigner les espèces concurrentes montre une capacité à paralyser les termites de manière irréversible. Concernant le venin de T. bicarinatum, deux peptides ont été isolés et identifiés par spectrométrie de masse. La bicarinaline, peptide de 20 acides aminés et amidé à son extrémité C-terminale, s'est démarqué par son action antibactérienne à large spectre. Testée sur deux souches de staphylocoques, ce peptide se révèle aussi efficace voire plus puissant que la méllitine, peptide antimicrobien du venin d'abeille. La bicarinaline apparaît comme un candidat potentiel pour la conception de nouveaux traitements antibiotiques
Animal venoms, by their biochemical richness and diversity of molecular targets, are a highly significant source of new molecules, with numerous potential applications. A major thrust of present pharmacological research now concerns drugs to replace certain antibiotics, proven ineffective due to the appearance of resistant strains. And discoveries of animal toxins over the past 40 years or more, have shown that venomous species could be the « pharmacists of the future », with only a few species of ants' venoms having been studied, but each time resulting in the description of original toxins. The aim of this thesis has been to study the venom of tropical ants using a multidisciplinary approach combining biochemical analysis and toxinology, centred on two main areas: (1) Research into their biological activity on insects and bacteria; (2) Fractionation of venoms using separative techniques, plus biochemical analysis of the peptides isolated using mass spectrometry. Two species of ant have been chosen based on their lifestyles: Crematogaster striatula is arboricolous and Tetramorium bicarinatum, terricolous, and the different biological activities of their crude venoms have been investigated using the MTT test. The Dufour liquid of C. striatula, in addition to its ability to scare away competitors, can definitively paralyse termites. For the venom of T. bicarinatum, two peptides have been isolated, and identified using mass spectrometry. Bicarinalin, a short 20 amino acid residues C-terminally amidated peptide, was notable for its wide spectrum antibacterial activity which, when tested on two Staphylococcus strains, proved to be at least if not more potent than mellitin, the antimicrobial peptide from bee venom. Bicarinalin would thus appear to be a good candidate for the development of new antibiotic drugs
8

Nguyen, Bao. "Étude et analyse de conopeptides de venins issus de cônes malacophages du Vietnam." Paris, Muséum national d'histoire naturelle, 2014. http://www.theses.fr/2014MNHN0016.

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Le venin de cônes (Conidae) constitue une source abondante de peptides bioactifs (conopeptides ou conotoxines). Dans cette thèse, nous avons comparé le venin de deux cônes malacophages: Conus bandanus et Conus marmoreus. En utilisant nano-LC ESI MS et MS/MS, nous mettons en évidence la présence de 92 peptides communs, ce qui représente 24,4% (de 376 peptides) et 18,4% (de 499 peptides) composant les venins de C. Bandanus et C. Marmoreus, respectivement. L'estimation des ponts disulfures révèle que 75% et 61% des conopeptides dans les venins de C. Bandanus et C. Marmoreus sont riches en ponts disulfures. Les mêmes séquences en acides aminés se retrouvent pour un certain nombre de conopeptides des deux espèces, qui montrent aussi des différences dans l’expression d’autres conopeptides. Nous avons également à partir du venin de C. Bandanus isolé, purifié et caractérisé les -BnIA/B/C/D (superfamille A), les BnIIIA/B/C/D/E (superfamille M), BnVA (superfamille T) et BnVIA (superfamille H)
Cone snail venoms (family Conidae) are a rich source of small bioactive peptides (conotoxins or conopeptides). In this thesis, we compared the venom of the two molluscivorous snails Conus bandanus and Conus marmoreus. Using nano-LC ESI MS and MS/MS we demonstrate the presence of 92 common peptides, representing 24,4% (out of 376 peptides) and 18,4% (out of 499 peptides) component in venoms of C. Bandanus and C. Marmoreus, respectively. The overall estimation of conopeptide disulphide bridges reveals 75% and 61% of “disulphide-rich” peptides in C. Bandanus and C. Marmoreus venom components, respectively. The same amino acid sequences were found for a number of peptides in the two species, which also show differences in the expression of other conopeptides. We also have isolated, purified and characterized novel conotoxins from C. Bandanus venom such as the -BnIA/B/C/D (A-superfamily), the BnIIIA/B/C/D/E (M-superfamily), BnVA (T-superfamily) and BnVIA (H-superfamily)
9

Leung, Kar Wah. "Ginseng pharmacology : signaling pathways of ginsenoside-Rg1 in human umbilical vein endothelial cells." HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/766.

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10

Boisvert, Étienne. "Îlots boisés en terre de grande culture : relictualité et biodiversité, l’exemple du Vexin français. Essai de biogéographie historique." Thesis, Paris 4, 2010. http://www.theses.fr/2010PA040147.

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L’objectif est de distinguer les îlots boisés relictuels des néoformés dans une matrice agricole, de les recenser avant de les caractériser et d’évaluer leur biodiversité et pour finir d’en tirer un modèle. La méthode associe le recours aux archives et aux photographies aériennes à l’enquête de terrain (1996-2007). L’approche cartographique s’est faite par analyse régressive (2004-1620). Le seuil temporel permet de reconnaître 152 îlots (<50ha) dont l’existence est attestée avant 1620. L’analyse régressive s’appuie sur le réseau viaire, élément fixe et structurant du paysage, pour cartographier les petits bois.On constate une forte relation entre la localisation des îlots relictuels, les tracés antiques et les chemins médiévaux. La caractérisation et l’évaluation de la biodiversité des relictuels s’effectuent selon une démarche spatio-temporelle pluriscalaire, et à partir d’une comparaison avec les îlots néoformés. L’analyse à partir de la canopée informe sur la texture de la couverture boisée et la dynamique du manteau forestier, sur les coupes, les lisières et le réseau viaire intraforestier. L’analyse de la structure interne porte sur la diversité taxinomique et la diversité écologique des espèces végétales et des espèces aviaires indicatrices. Ces analyses font apparaître la spécificité des relictuels, dont est proposé un modèle. Il s’agit soit de fragments de forêts anciennes, soit en plus grand nombre de formations boisées secondaires mais anciennes, gallo-romaines, mérovingiennes ou médiévales
The purpose is to distinguish the relictual forest islands from the recent ones in an agricultural matrix; to inventory and characterize them and to assess their biodiversity, and eventually to develop a model. The method combines the resort to archives and aerial photographs with field studies (1996-2007). The mapping approach has been based on regression analysis (2004-1620). The time threshold has made it possible to identify 152 woodlots (<50ha) which presence was attested before 1620. The regression analysis to map the wood patches has been based on the path network, which is a fixed and structuring element of the landscape. There is a strong relation between the location of the relictual forest islands, the antique tracks and the medieval paths. The characterization and assessment of the relictual forest islands biodiversity have been carried out following a time and space pluri-scalar approach and from a comparison with recent forest islands. The analysis was based on the shapeless canopy, the texture and dynamics of the forest cover, the cuttings, the edges and the internal forest path network. The analysis of the internal structure focuses on the taxonomic diversity and the ecological diversity of the plant species and the indicator bird species. These analyses have stressed the specificity of the relictual forest islands, a model of which has been developed. They are either fragment of ancient forests, or, in most cases, secondary but old forest forms from the Gallo-Roman, Merovingian or medieval time
11

Horner, Daniel. "Isolated distal deep vein thrombosis in symptomatic ambulatory patients : a prospective data analysis and therapeutic feasibility study." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/isolated-distal-deep-vein-thrombosis-in-symptomatic-ambulatory-patients-a-prospective-data-analysis-and-therapeutic-feasibility-study(02979c49-ec26-4099-b0f8-3da2acbf0672).html.

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Isolated distal deep vein thrombosis (IDDVT) is a condition recently suggested to be a different entity to that of proximal disease. There is currently little evidence defining the clinical importance of detection and treatment. International guidelines vary regarding management advice.An observational cohort study, prospective service evaluation and pilot randomised controlled trial were performed within a United Kingdom ambulatory thrombosis service. This project aimed to describe the burden of disease and explore three poorly researched aspects of IDDVT assessment and management: whole-leg compression ultrasound (CUS) performed by non-physicians within an ambulatory framework as a principal diagnostic modality; clinical presentation data and risk profile in comparison to that of proximal disease; the feasibility of further interventional randomised research and the risk/benefit profile of therapeutic anticoagulation.Within this ambulatory cohort, IDDVT accounted for 49.7% of acute thrombosis and differed significantly to proximal disease regarding provocation and symptomatology at clinical presentation. A negative whole-leg CUS excluded deep vein thrombosis with an adverse event rate (diagnosis of symptomatic venous thromboembolism during the 3 month follow up period) of 0.47% (95% CI 0.08 to 2.62). Future interventional research was proved feasible within an ambulatory setting.The randomised controlled trial conducted within this project is the largest to date comparing therapeutic anticoagulation against conservative strategy for the management of acute IDDVT. Patients allocated to therapeutic anticoagulation had significantly less overall propagation of thrombus (Absolute risk reduction [ARR] 25.7%, 95% Confidence interval 5.9 to 44.3 p<0.01), less short-term symptomatic progression (ARR 16.7%, 95% CI 2.6 to 32.1 p=0.05) and a result trending towards significance for reduction in serious thromboembolic complications (ARR 11.4%, 95% CI -1.5 to 26.7 p=0.11).IDDVT is a condition of equal prevalence to proximal venous thrombosis, which varies significantly regarding risk profile and clinical presentation. Using a single whole leg CUS reported by a non-physician within an emergency department pathway is associated with a low adverse event rate. This contemporary data also suggests that therapeutic anticoagulation is beneficial for reduction of short-term complications in IDDVT. The risk of false positive diagnosis and excess anticoagulation remains.This data can inform and direct future design of adequately powered randomised studies, in order to attempt external validation of these findings.
12

Paul, Timir, Samit Bhatheja, Hemang Panchal, Shimin Zheng, Subhash Banerjee, Sunil V. Raso, Luis Guzman, et al. "Outcomes of Saphenous Vein Graft Intervention With and Without Embolic Protection Device: A Comprehensive Review and Meta-Analysis." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/2771.

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Background: Current guidelines give a class I recommendation to use of embolic protection devices (EPD) for saphenous vein graft (SVG) intervention; however, studies have shown conflicting results. The objective of this meta-analysis is to compare all-cause mortality, major adverse cardiovascular events, myocardial infarction (MI), or target vessel revascularization in SVG intervention with and without EPD. Methods and Results: Literature was searched through October 2016. Eight studies (n=52 893) comparing SVG intervention performed with EPD (n=11 506) and without EPD (n=41 387) were included. There was no significant difference in all-cause mortality (odds ratio [OR], 0.79; confidence interval [CI], 0.55–1.12; P=0.19), major adverse cardiovascular events (OR, 0.73, CI, 0.51–1.05; P=0.09), target vessel revascularization (OR, 1.0; CI, 0.95–1.05; P=0.94), periprocedural MI (OR, 1.12; CI, 0.65–1.90, P=0.69), and late MI (OR, 0.80; CI, 0.52–1.23; P=0.30) between the 2 groups. Sensitivity analysis excluding CathPCI Registry study showed no difference in periprocedural MI, late MI, and target vessel revascularization; however, it favored EPD use in all-cause mortality and major adverse cardiovascular events. Further sensitivity analysis including only observational studies revealed no difference in all-cause mortality, major adverse cardiovascular events, target vessel revascularization, and late MI. Additional analysis after excluding CathPCI Registry study revealed no difference in outcomes. Conclusions: This study including 52 893 patients suggests no apparent benefit in routine use of EPD during SVG intervention in the contemporary real-world practice. Further randomized clinical trials are needed in current era to evaluate long-term outcomes in routine use of EPD, and meanwhile, current guideline recommendations on EPD use should be revisited.
13

Trépanier, Marie-Laurence. "Les performances du langage dans "La fabrique de cérémonies" et "L'ombre des choses à venir" de Kossi Efoui." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/29474.

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Ce mémoire vise à analyser les performances du langage, c’est-à-dire sa thématisation et ses effets dans les romans La fabrique de cérémonies et L’ombre des choses à venir de Kossi Efoui. Dans le premier chapitre, il s’attache à exposer les principaux discours que l’auteur convoque dans ses œuvres et à montrer de quelle manière ils s’articulent à l’Histoire : Histoire de la traite des Noirs, de l’esclavage, de la colonisation et de l’évangélisation des pays africains, et Histoire d’une culture qui s’est imposée en valorisant un ordre mondial néolibéral. Les discours en circulation dans la société du texte se caractérisent par leur visée manipulatrice. Ils travestissent la réalité et témoignent d’un désir de domination qui empiète sur les droits fondamentaux des hommes. Le second chapitre examine quant à lui les stratégies littéraires par lesquelles l’auteur déconstruit ces discours manipulateurs et dénonce les absurdités du monde social. Théâtralisation de la narration, ironie, intertextualité et métatextualité sont autant d’éléments d’une écriture subtile, qui dévoile en même temps qu’elle voile ses enjeux critiques.
14

Lam, In Kei. "Anti-angiogenic activities of flavonoids from Pericarpium Citri Reticulatae on human umbilical vein endothelial cells (HUVECs) and zebrafish." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2447360.

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15

Venn, Ronald [Verfasser], and Nicola [Akademischer Betreuer] Berg. "Partnering for Sustainable Value Creation : Conceptual and Empirical Analyses of Co-Creation in Cross-sector Social Partnerships at the Base of the economic Pyramid / Ronald Venn. Betreuer: Nicola Berg." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://d-nb.info/1078408955/34.

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16

Watanabe, Yuji, Gerhard P. Püschel, Andreas Gardemann, and Kurt Jungermann. "Presinusoidal and proximal intrasinusoidal confluence of hepatic artery and portal vein in rat liver : functional evidence by orthograde and retrograde bivascular perfusion." Universität Potsdam, 1994. http://opus.kobv.de/ubp/volltexte/2008/1670/.

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The site of confluence of the artery and the portal vein in the liver still appears to be controversial. Anatomical studies suggested a presinusoidal or an intrasinusoidal confluence in the first, second or even final third of the sinusoids. The objective of this investigation was to study the problem with functional biochemical techniques. Rat livers were perfused through the hepatic artery and simultaneously either in the orthograde direction from the portal vein to the hepatic vein or in the retrograde direction from the hepatic vein to the portal vein. Arterial how was linearly dependent on arterial pressure between 70 cm H2O and 120 cm H2O at a constant portal or hepatovenous pressure of 18 cm H2O. An arterial pressure of 100 cm H2O was required for the maintenance of a homogeneous orthograde perfusion of the whole parenchyma and of a physiologic ratio of arterial to portal how of about 1:3. Glucagon was infused either through the artery or the portal vein and hepatic vein, respectively, to a submaximally effective ''calculated'' sinusoidal concentration after mixing of 0.1 nmol/L. During orthograde perfusions, arterial and portal glucagon caused the same increases in glucose output. Yet during retrograde perfusions, hepatovenous glucagon elicited metabolic alterations equal to those in orthograde perfusions, whereas arterial glucagon effected changes strongly reduced to between 10% and 50%. Arterially infused trypan blue was distributed homogeneously in the parenchyma during orthograde perfusions, whereas it reached clearly smaller areas of parenchyma during retrograde perfusions. Finally, arterially applied acridine orange was taken up by all periportal hepatocytes in the proximal half of the acinus during orthograde perfusions but only by a much smaller portion of periportal cells in the proximal third of the acinus during retrograde perfusions. These findings suggest that in rat liver, the hepatic artery and the portal vein mix before and within the first third of the sinusoids, rather than in the middle or even last third.
17

Dressel, Bárbara. "Analyse structurale, pétrologique et métallogénique de la minéralisation aurifère néoprotérozoïque du Granite de Passa Três, Campo Largo – PR, Sud du Brésil : implications sur les relations granite/minéralisation." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTG023.

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Le Granite Passa Três est situé à l'Est de l'Etat du Paraná, au Sud du Brésil, et est allongé selon une direction NNE-SSW. Sa mise en place se fait au cœur des metapélites mesoprotérozoïques du Groupe Açungui (Province Mantiqueira). La minéralisation d’or du Granite Passa Três est composée par des veines de quartz contenant des quantités variables de fluorite, sulfures et carbonates. Les objectifs principaux de ce travail de thèse sont : de comprendre le modèle de formation du système de veines minéralisées en prenant en compte les relations entre magmatisme, hydrothermalisme, déformation et minéralogie à la fois dans l’espace et dans le temps ; la caractérisation de la nature, de la source et des conditions de dépôt des fluides ; et la caractérisation du modèle métallogénique de ce gisement singulier. Pour arriver à ces objectifs, les méthodes utilisées seront, en sus de la géologie structurale et de terrain : la pétrographie, la géochronologie U-Pb (LA-ICP-MS) sur zircon et 40Ar-39Ar sur muscovite, la microscopie électronique à balayage (MEB), la microsonde électronique, la fluorescence X (XFR), l’analyse isotopique du soufre (δ34S) et l’analyse microthermométrique et RAMAN des inclusions fluides. Les données structurales ont montré la coexistence de deux systèmes principaux de filons minéralisés, l’un N-S et l’autre E-W, avec des pendages de 60-75°W et 45-70°S, respectivement. Les deux systèmes sont interprétés comme contemporains et conjugués. Les corps minéralisés forment des géométries sigmoïdales qui résultent de l’ouverture en pull-aparts résultant de mouvements en faille normale le long de plans de glissement à faible pendage. Le fort pendage des structures minéralisées s’explique par l’enveloppe globale formée par la succession des pull-aparts. Quatre étapes minéralogiques sont à l’origine de la formation du système minéralisé : phase 1 [qtz 1 + fl], phase 2a [qtz 2 + py 2a ± or ± cpy ± aik ± fl ± sph ± musc], phase 2b [qtz 2 + py 2b + or + cpy + aik + ank ± sph ± fl ± musc] et phase 3 [qtz 3 + ank + calc + molyb ± aik ± musc ± fl]. L’or se trouve dans la forme d’or invisible et d’or natif dans des fractures qui affectent les pyrites des phases 2a et b, systématiquement associé avec la chalcopyrite et l’aikinite. L’altération associée à la minéralisation inclue des assemblages composés par muscovite/quartz/pyrite (altération du type greisen) et séricite/carbonate/clinochlore (altération phyllique). Les valeurs δ34S des pyrites (de -0.1‰ à 1.1‰) indiquant que le soufre du dépôt peut être d’origine magmatique. Cette hypothèse est en accord avec l’observation systématique, dans les parties supérieures du granite (sondage et niveaux supérieurs de la mine), de structures caractéristiques de transition magmatique-hydrothermale comme des systèmes aplo-pegmatitiques, des veines de quartz à bordure de K-feldspath, des concentrations de quartz de type stockscheider et des textures de solidification unilatérales (UST). Les résultats de géochronologie confirment cette hypothèse avec des âges U-Pb sur zircon (611.9±4.7 et 611.9±5.6 Ma pour le granite à grain moyen (GEM) et le microgranite (GEF) et 40Ar-39Ar sur muscovite (veines à bordure de K-feldspath : 612.9±2 à 608.8±2 Ma ; veines minéralisées : 611.7±2 à 608.8±2 Ma ; veines de quartz précoces : 608.4±2 Ma) très proches. Ces âges obtenus indiquent que la mise-en-place du granite, l’exsolution du fluide magmatique-hydrothermal et la formation des veines de quartz aurifères ont été réalisées pendant un écart de temps de 5 Ma, entre 613 et 608 Ma. La minéralisation (611 à 608 Ma) contemporaine de la cristallisation du granite (612 à 610 Ma), l’association de l’or avec des minéraux de bismuth (aikinite), la démonstration du contrôle structural sur la formation des veines et les évidences de transition magmatique-hydrothermale en domaine de coupole granitique montrent que le dépôt d’or du Granite Passa Três partage plusieurs similitudes avec les dépôts du type intrusion-related
The Passa Três Granite is situated in southern Brazil (Paraná State) and presents a NNE-SSW elongated shape. This intrusion is emplaced within metapelites of the Mesoproterozoic Açungui Group (Ribeira Belt, Mantiqueira Province), between the N40E trending Morro Agudo and Lancinha faults. Gold mineralisation is composed of centimetric to metric quartz veins with fluorite, sulphides and carbonates. The main objectives of this work are i) to understand the model of formation of the mineralised veins systems taking into account the relationships between magmatism, hydrothermalism, deformation and mineralogy in space and time; ii) the characterization of the nature, source and emplacement conditions of the ore fluids; and iii) the characterization of a metallogenic model for this singular deposit. In order to reach these purposes, the methods to be applied include, beyond the structural geology and field works: petrography, U-Pb zircon (LA-ICP-MS) and 40Ar-39Ar muscovite geochronology, scanning electron microscopy (SEM), electron-microprobe analyses (EPMA), X-ray fluorescence (XRF), isotopic analysis of sulphur (δ34S), and microthermometric and Raman analysis of fluid inclusions. Structural data showed the coexistence of two major normal mineralised vein systems, one N-S and the other one E-W, with dips of 60-75ºW and 45-70ºS, respectively. Both systems are interpreted to be contemporaneous and conjugated. Orebodies form sigmoidal geometries that resulted of the opening of pull-aparts as a consequence of the normal movements along low-angle fault planes. High-angle dip of the global mineralised structures is explained by the succession of the pull-aparts. Four mineralogical stages resulted in the formation of the mineralised system: phase 1 [quartz 1 + fluorite], phase 2a [quartz 2 + pyrite 2a ± gold ± chalcopyrite ± aikinite ± fluorite ± sphalerite ± muscovite], phase 2b [quartz 2 + pyrite 2b + gold + chalcopyrite + aikinite + ankerite ± sphalerite ± fluorite ± muscovite] and phase 3 [quartz 3 + ankerite + calcite + molybdenite ± aikinite ± muscovite ± fluorite]. Gold occurs as invisible gold and as native grains within fractures that affect pyrite 2a and 2b, commonly associated with chalcopyrite and aikinite. Alteration related to the mineralisation includes muscovite/quartz/pyrite (greisen type alteration) and sericite/carbonato/clinochlore (phyllic alteration) assemblages. The δ34S values of pyrite crystals (from -0.1‰ to 1.1‰) indicate that the sulphur in this deposit may have a magmatic origin. This hypothesis agrees with the systematic observation, within the upper part of the granite (drill holes and superior levels of the mine), of structures typical of magmatic-hydrothermal transition such as aplite-pegmatite systems, quartz veins with K-feldspar border, quartz concentration of stockscheider type and unilateral solidification textures (UST). Geochronological data confirm this hypothesis with U-Pb zircon ages (611.9±4.7 and 611.9±5.6 Ma for medium grained granite facies (GEM) and microgranite (GEF), respectively) and 40Ar-39Ar muscovite dating (veins with K-feldspar border: 612.9±2 to 608.8±2 Ma; mineralised veins: 611.7±2 to 608.8±2 Ma; barren vein: 608.4±2 Ma), that are very close. These ages indicate that the granite emplacement, the magmatic-hydrothermal fluid release and the formation of gold-bearing quartz veins occur during a time lapse of approximately 5 Ma, between 613 and 608 Ma. The mineralisation (611 to 608 Ma) coeval to granite crystallization (612 to 610 Ma), the association of gold with Bi minerals (aikinite), the strong structural control for veins and magmatic-hydrothermal transition features at the roof of a small granitic intrusion suggest that the Passa Três gold deposit shares several similarities with intrusion-related gold deposits
18

Borin, Thaiz Ferraz. "Aumento da IL-1beta no processo de arterialização de enxertos venosos utilizando modelos ex vivo, in vitro e in vivo." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-29012009-132853/.

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A revascularização cardíaca utilizando a ponte de safena é um procedimento bastante comum usado para restabelecer o fluxo coronariano. O sucesso do implante depende da adaptação do vaso que estava em um regime hemodinâmico venoso, e passa subitamente para um regime arterial. Durante este processo adaptativo, ocorrem diversas alterações moleculares cujo conhecimento pode fornecer alternativas de melhoramento da patência dos enxertos venosos em leito arterial. Neste trabalho está sendo investigada a regulação da IL-1beta tanto em veia safena humana como em modelo animal de arterialização venosa. A IL-1beta mostrou-se aumentada em veia safena humana arterializada tanto in vivo como ex vivo. Interessantemente, este aumento observado nos dias iniciais (1-5 dias) parece diminuir em tempos mais tardios (1-4 anos). Em modelo de arterialização de rato foi observado aumento de 12 vezes na expressão da IL-1beta após o primeiro dia de arterialização com diminuição posterior, mantendo-se em torno de 2 vezes maior em comparação a veia jugular normal. Além da regulação temporal da IL-1beta, foram também acompanhadas as alterações morfológicas que ocorrem durante o processo de arterialização venosa. Observou-se uma redução gradual de células musculares lisas (SMC) que quase desaparecem 3 dias após a cirurgia. Esta perda celular pode estar relacionada ao pico de apoptose observado já no primeiro dia de arterialização. Após 7 dias as SMC reaparecem, porém, de maneira ainda desorganizada. Concomitante com o reaparecimento das SMC observou-se progressivo espessamento da camada média, assim como surgimento de uma camada neoíntima. A IL-1beta, devido ao seu padrão de regulação assim como sua localização durante o processo de arterialização, pode estar relacionada com as alterações estruturais verificadas na arterialização do enxerto. Estratégias de intervenção modulando a atividade da IL-1beta poderão fornecer indicativos da sua participação no remodelamento do enxerto venoso. Em conjunto, demonstramos que o modelo de arterialização de segmento venoso em rato reproduz várias das alterações morfológicas descritas na doença do enxerto venoso em humanos e por isso será útil na caracterização de genes candidatos que participam deste processo. A IL-1beta tem sua expressão aumentada em segmento venoso arterializado in vivo e ex vivo, podendo representar um interessante alvo para aplicação de metodologias de intervenção visando influenciar a adaptação de enxertos venosos com finalidade terapêutica
The vein graft is subjected to increased tensile stress and the complex adaptive vein response to the arterial hemodynamic condition may predispose to bypass failure in some individuals. The understanding of molecular changes underlying this process may be useful for the development of novel therapeutical interventions to increase the vein graft patency. In this work, we investigated the early effect of arterialization on the expression of IL-1beta gene in human saphenous vein and the time-course regulation in rat arterialization model. IL-1beta is upregulated in early stage of human saphenous vein arterialization in vivo and ex vivo. This increase is also observed in arterialized rat jugular vein which showed IL-1beta expression 12 times higher on day 1 compared to normal jugular vein. Later, the IL-1beta levels decreases and maintain the level about twice above normal jugular vein. Moreover, it is observed gradual reduction of smooth muscle cells (SMC), which almost disappeared on the 3rd day after surgery. Apoptosis, which is markedly increased on the 1st day, appears to be an important event during this process. At the 7th day, cellular density and SMC proliferation gradually increased till the 90th day. There was a gradual thickening of the medial layer and formation of neointima with deposition of SMC in the subendotelial layer from day 7 on. Initially the medial layer appeared disorganized, day 7 to 14, then by day 28 it became more organized and the presence of an intimal layer with SMCs was evident. The neointimal layer increased gradually from day 7 on. These results provide evidence that the modulation of IL-1beta activity may be an interesting target to be explored I the future to increase the vein graft patency. Altogether, we demonstrate that the model of arterialization of venous segment in rat reproduces several of the morphological changes described in the venous graft disease in humans and thus will be useful in characterization of candidate genes involved in this process and testing them as a potential therapeutic targets. The IL-1beta expression is increased after 1 day of arterialization of vein segment in vivo and ex vivo and shall be an interesting target to be tested to influence the adaptation of venous grafts for therapeutic purpose
19

Wiberg, Steen Tobias. "Genetic relationships and origin of the Ädelfors gold deposits in Southeastern Sweden." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67912.

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Ädelfors is situated ca 17 km east of Vetlanda, Jönköping County, in the N-S striking Trans-scandinavian igneous belt and is a part of the NE-SW striking 1.83-1.82 Ga Oskarshamn-Jönköping belt emplaced during a continental subduction towards the Svecofennian continental margin. The continental arc hosts the 1.83 Ga metasedimentary Vetlanda supergroup composed of foliated metagreywacke, metasandstone and metaconglomerate. The sequence is intercalated by mafic and felsic volcanites and hosts the Cu-Au-Fe-mines at Ädelfors. Ädelfors mining field consists of ca 330 mineralized quartz veins hosting both copper, gold and iron. The iron mines Nilsson’s iron mine (NFE) and Fe-mine (FE), the copper mine Kamelen (KM) and the gold mines Brånad’s mine (BR), Adolf Fredrik’s mine (AF), Old Kron mine (GKR), Old Kolhag’s mine (GKO), Thörn mine (TH), New Galon mine (NG), Stenborg’s mine (ST), Tysk mine (TG), Hällaskallen (HS) and Fridhem (FR) have been investigated to deduce a possible genetic relation between the veins and their origin. Sulfur isotope ratios have also been conducted on pyrite from KM, AF and FE. The veins can stucturally be divided into several groups. AF, GKR, ST, NG, TH and possibly NFE are striking 10-70° with a dip of 55-70°. BR, GKO and KM are striking 110-140° with a dip of 80-90° whereas TG and HS strike 90-110° dipping 85°. Fridhem, being distal to the other mines, strikes 70° and dips 80°. A chlorite-quartz-biotite-sericite-rich metapelite hosts the veins in all localities except; FR where a layered, beresitizised felsic volcanite rich in plagioclase, sericite, biotite and quartz hosts disseminated pyrite; and NFE, HS and NG which are hosted by a mafic tuffite. Quartz veins are mainly milky and equigranular, exceptions are FE with black pyrite-bearing quartz veins, cutting through the banded magnetite-metapelite and KM with its dynamically recrystallized quartz. Chlorite-, zeolite-, carbonate-, hematite-, amphibole-, kalifeldspar-, sericite-, biotite- and epidote alteration has been observed among the localities. The ore minerals are dominated by: fractured sub- to euhedral pyrite in cataclastic aggregates or selvage bands, interstitial chalcopyrite in pyrite, marcasite, pyrrhotite, gold and sporadic chalcopyrite diseased sphalerite and arsenopyrite. Previously not reported tetradymite, staurolite, galena and Ce-monazite have also been observed. Bismuthinite and tetradymite as inclusions in pyrite were observed in AF, GKR, FR and TG. Gold was observed in AF, BR, GKR and TG as inclusions in pyrite or quartz with a Au/Ag median of 78.41. HS distinguishes itself with Au/Ag ratios of 4.66-5.25. The trace element ratios in pyrite reveal two major types of pyrite. 1) found in FE and KM (pyrite type 1) with Co/Ni ratio of 10.94, Bi/Au of 1.79, Bi/S of 0.037, Au/Ag of 11.13, S/Se of 235.96 and As/S of 0.006. 2) found in NG, GKO, ST, TH, AF, NFE, HS, GKR, BR, FR, TG and as stringers in KM4 py1 pyrite type 2) with an average Co/Ni ratio of 5.26, Bi/Au of 1.95, Bi/S of 0.031, Au/Ag of 4.19, S/Se of 0 and As/S of 0. δ34S values strengthens this grouping as KM and FE has 1,3-2,6 ‰ and AF 3,6-3,8 ‰. The following geological interpretation has been concluded: The banded iron formation in FE is the earliest mineralization and was later fractured, emplacing quartz veins with pyrite of type 1. During this event, the Cu-vein in KM was also formed. A second generation of fractures, emplaced after the Småland granitoids formed, were filled with quartz and pyrite of type 2 at mesozonal depth. This is the main stage of gold mineralization and includes NG, GKO, ST, TH, AF, NFE, GKR, BR, FR and TG. During this event, pyrite of type 2 was added to KM, causing recrystallizing of the quartz. HS is possibly emplaced last or altered as it is more enriched in silver. Morphology, mineralogy, alterations, mineral chemistry and sulfur isotope signatures indicates an orogenic origin of the gold-rich quartz veins at Ädelfors as well as the copper-rich vein in KM.
Ädelfors ligger ca 17 km öster om Vetlanda, Jönköpings län, i det N-S strykande Transskandinaviska granit och porfyrbältet och är en del av det NÖ-SV strykande 1,83-1,82 Ga Oskarshamn-Jönköpingsbältet (OJB) bildad i en kontinental subduktionszon i kanten av den Svecofenniska kontinentalplattan. I denna kontinentalbåge ligger Vetlanda supergruppen som är en metasedimentär del av OJB bestående av starkt folierad 1,83 Ga metagråvacka, metasandsten och metakonglomerat med inlagringar av mafiska och felsiska vulkaniter. Ädelfors gruvfält består utav ca. 330 kvartsgångar förande mestadels guld men också koppar. Järnmineraliseringar i form av bandad järnmalm finns också i området. Geologin, mineralogin och pyritens kemiska sammansättning från järngruvorna Nilssons järngruva (NFE) och Fe-gruvan (FE), koppargruvan Kamelen (KM) och guldgruvorna Brånadsgruvan (BR), Adolf Fredriks gruva (AF), Gamla Krongruvan (GKR), Gamla Kolhagsgruvan (GKO), Thörngruvan (TH), Nya Galongruvan (NG), Stenborgs gruva (ST), Tyskgruvan (TG), Hällaskallen (HS) och Fridhem (FR) har undersökts för att finna eventuella genetiska likheter. Svavelisotopförhållande har fastställts för pyrit från AF, FE och KM. Strukturellt kan gångarna delas in i ett antal grupper. AF, GKR, ST, NG, TH och möjligtvis NFE stryker 10-70° och stupar 55-70°. BR, GKO och KM stryker 110-140° och stupar 80-90° medan TG och HS stryker 90-110° och stupar 85°. Fridhem stryker 70° och stupar 80°. En klorit-kvarts-sericit-biotitrik metapelit utgör värdbergarten i alla gruvor förutom; FR där den utgörs av en beresitiserad felsisk vulkanit rik på plagioklas, sericit, biotit och kvarts med disseminerad pyrit; och NFE, HS, NG vilka har en mafisk tuffitisk moderbergart. Kvartsgångarna är mjölkvita med undantag för FE:s svarta, pyritförande kvarts vilket uppträder som sprickfyllnad i den bandade järnmalmen och är senare bildad. Kvartsen i KM är starkt dynamiskt omkristalliserad. Svag till måttlig foliation är vanlig i sidoberget med undantag av stark foliation i TG och NFE, vilka är lokaliserade i förkastningssprickor med stark kloritförskiffring av värdbergarten. Klorit-, zeolit-, karbonat-, hematit-, amfibol-, kalifältspat-, sericit-, biotit- och epidotomvandling förekommer i majoriteten av lokalerna. Malmmineralen är dominerande sprött deformerad subhedral till euhedral pyrit som kataklastiska aggregat eller band, interstitiell kopparkis i pyrit, markasit, magnetkis, guld och sporadiskt kopparkissjuk zinkblände och arsenikkis. I det här arbetet har även tetradymit, staurolit, blyglans och Ce-monazit observerats. Bismutinit och tetradymit i form av inneslutningar i pyrit observerades i AF, GKR, FR och TG. Guld observerades i AF, BR, GKR och TG som inneslutningar i pyrit eller fritt i kvarts med Au/Ag medianvärde på 78,41, avvikande är HS med värden mellan 4,66-5,25.    Förhållanden mellan spårelement i pyrit indikerar två typer av pyrit. Typ 1 funnen i FE och KM har följande värden: Co/Ni = 10,94, Bi/Au = 1,79, Bi/S = 0,037, Au/Ag = 11,13, S/Se = 235,96 och As/S = 0,006. Typ 2 funnen i NG, GKO, ST, TH, AF, NFE, HS, GKR, BR, FR, TG och som sliror i KM4 py1 har följande värden Co/Ni = 5,26, Bi/Au = 1,95, Bi/S = 0,031, Au/Ag = 4,19, S/Se = 0 and As/S = 0. δ34S värden styrker denna uppdelning där KM och FE har värdena 1,3-2,6 ‰ och AF 3,6-3,8 ‰. Den geologiska utvecklingen av fältet har tolkats som följande: FE-gruvans bandade järnmalm är den tidigaste mineraliseringen vilket följs utav uppsprickning och läkning av kvarts med pyrit typ 1 som också bildar kopparmineraliseringen KM. Senare sprickzoner efter Smålandsgraniternas intrusion läks av kvarts med pyrit typ 2 på mesozonalt djup vilket bildar NG, GKO, ST, TH, AF, NFE, GKR, BR, FR, TG och omkristalliserar och introducerar nya pyritsliror i kvartsen i KM. HS bildas möjligtvis sist eller har blivit omvandlad eftersom den är anrikad på silver. Morfologi, omvandlingar och svavelisotop-signaturer tyder på ett orogent ursprung för Ädelfors guldrika kvartsådror samt den kopparrika kvartsådern i KM.
20

Wu, Chia-Ying, and 吳佳穎. "Molecular interactions among Rep protein and genomic DNA of ageratum yellow vein virus Ping-Tung strain and analyses of replication in prokaryotic system." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/47536085080349520695.

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碩士
國立中興大學
農業生物科技學研究所
90
Abstract The replication ability is one of the key determinants for surviving of viruses. The Rep protein, the first expressed by geminiviruses during the early infection stage, is the only virus-encoded protein required for the replication process, including specific cleavage and ligation to initiate and terminate rolling-circle replication, self-interaction, and regulation of the host cell cycles. In this research, the monopartite begomovirus, ageratum yellow vein virus Ping-Tung strain (AYVV-PT) was used to investigate the interactions between Rep proteins and viral DNAs and to develop the prokaryotic replication system based on E.coli/phage M13 to facilitate the study of geminivirus replication. The Rep gene of AYVV-PT was cloned into plasmid pETBlue for expression, and gel-purified Rep proteins were used for producing specific polyclonal antibodies. The Rep gene was further sub-cloned into plasmid pGEX-4T-1 to obtain Rep proteins in native condition by affinity chromatography. The interactions between Rep proteins and viral genomic DNAs were investigated by Nucleoprotein Binding-ELISA (NB-ELISA) and Southwestern blot analyses. Rep protein has the highest affinity to nt. 1522-2731 of AYVV-PT genome under the optimized in vitro binding condition, 20 mM Tris-HCl buffer, pH 7.4 containing 0.4-0.6 % NaCl. The full-length AYVV-PT genome was cloned into phage M13 as a single unit, and specific Digoxygenin-labeled RNA and DNA probes for AYVV-PT were prepared by in vitro transcription and asymmetric PCR. The signals of small DNAs co-migrating with the single-stranded, circular DNAs encpasidated in virus particles were detected by Southern blot analysis, and the accumulation of the small DNAs was revealed by time course analysis. In addition, the small DNAs were further confirmed as single-stranded, circular DNA of AYVV-PT by RNase A, S1 nuclease digestions and PCR followed by nucleotide sequence analysis. The results suggested that the prokaryotic replication machinery of E.coli/phage M13 could support the generation of single-stranded, circular DNA of AYVV-PT in a construct containing only one copy of replication origin and a single unit viral genome. The E.coli/phage M13 system may facilitate the study of geminivirus replication and the development of convenient infection and foreign gene expression systems.
21

Brass, Margaret Mary. "Biomechanical and morphological characterization of common iliac vein remodeling: Effects of venous reflux and hypertension." Thesis, 2014. http://hdl.handle.net/1805/5278.

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Indiana University-Purdue University Indianapolis (IUPUI)
The passive properties of the venous wall are important in the development of venous pathology. Increase in venous pressure due to retrograde flow (reflux) and obstruction of venous flow by intrinsic and extrinsic means are the two possible mechanisms for venous hypertension. Reflux is the prevailing theory in the etiology of venous insufficiency. The objective of this thesis is to quantify the passive biomechanical response and structural remodeling of veins subjected to chronic venous reflux and hypertension. To investigate the effects of venous reflux on venous mechanics, the tricuspid valve was injured chronically in canines by disrupting the chordae tendineae. The conventional inflation-extension protocol in conjunction with intravascular ultrasound (IVUS) was utilized to investigate the passive biomechanical response of both control common iliac veins (from 9 dogs) and common iliac veins subjected to chronic venous reflux and hypertension (from 9 dogs). The change in thickness and constituent composition as a result of chronic venous reflux and hypertension was quantified using multiphoton microscopy (MPM) and histological evaluation. Biomechanical results indicate that the veins stiffened and became less compliant when exposed to eight weeks of chronic venous reflux and hypertension. The mechanical stiffening was found to be a result of a significant increase in wall thickness (p < 0.05) and a significant increase in the collagen to elastin ratio (p < 0.05). After eight weeks of chronic reflux, the circumferential Cauchy stress significantly reduced (p < 0.05) due to wall thickening, but was not restored to control levels. This provided a useful model for development and further analysis of chronic venous insufficiency and assessment of possible intervention strategies.
22

Ramaniuk, Volha. "Růst Mycobacterium smegmatis na agarovém médiu a agarovém médiu pokrytém celofánovou folií - morfologická a proteomová studie." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-305796.

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Biofilm formation is one of the most common bacterial survival strategies. Majority of bacterial species are able to form these three-dimensional structures, including pathogens like Mycobacterium tuberculosis. Representatives of Mycobacterium genus widely occur in the nature, although they can cause serious problems when they appear in medical equipment and artificial replacements of the human body. Non-pathogenic Mycobacterium smegmatis mc2 155 was used as a model organism in our experiments. We investigated morphology of the three- and six-day-old colonies (in fact biofilms) on agar and agar covered with cellophane using Stereo microscope and Scanning Electron Microscope. We found that a type of surface as well as a carbon source has a great influence on the morphology of the M. smegmatis colonies. We isolated proteomes from the agar and cellophane cultures and from planktonic culture. Two-dimensional electrophoresis was used as the main proteomic method. Proteomic data were analyzed using PDQuest software. Then the sets of proteins detected by qualitative and quantitative analyses were compared using Venn diagrams. As a result, we recognized 7 unique proteins that might be specific for recognition and adhesion of bacteria to the cellophane, no unique protein in agar proteome and 46 unique...

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