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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Morfologia de ovos, larvas e adultos de Paratanaisia bragai (Santos, 1934) Freitas, 1959 (Digenea, Eucotylidae) e histopatologia do rim de Columba livia (Gm.) infectado / Morphology of eggs, larvae and adult of Paratanaisia bragai (Santos, 1934) Freitas, 1959 (Digenea, Eucotylidae) and histopathology of the kidney Columba livia infected

XAVIER, Vanessa Barreto 24 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-06T20:04:45Z No. of bitstreams: 1 2015 - Vanessa Barreto Xavier.pdf: 10480934 bytes, checksum: dcefb748f49bc38601b8bbc19c70ebc8 (MD5) / Made available in DSpace on 2017-06-06T20:04:45Z (GMT). No. of bitstreams: 1 2015 - Vanessa Barreto Xavier.pdf: 10480934 bytes, checksum: dcefb748f49bc38601b8bbc19c70ebc8 (MD5) Previous issue date: 2015-02-24 / CAPES / Paratanaisia bragai is a digenetic that reaches sexual maturity in the collecting ducts of domestic and wild birds, and larval development using the snail Subulina octona or Leptinaria unilamellata. The embryonated eggs are released with the waste products of the definitive host and the infection settles in the snail by ingestion of these. After hatching, the miracidium, develop inside the snail two sporocysts generations, cercariae and metacercariae. The definitive host acquires infection by ingestion of parasitized snail. The present study was aimed to identify the action of the parasite on the kidney of pigeons, Columba livia, through histology, and the morphometry, morphology and ultrastructure using light microscopy, scanning electron and transmission of the egg, larval stages (miracidium , cercariae and metacercariae) and adult helminth P. bragai. The adults pigeons were obtained near the Central de Abastecimento do Estado do Rio de Janeiro S.A, Iraj?, Munic?pio do Rio de Janeiro. After parasitological examination in the laboratory, to check infection, the pigeons infected were necropsied to collect helminth and infected kidney. The pigeons were used as uninfected controls. The experimental protocols were approved by the ethics committee on research UFRRJ. Histopathology showed dilatation of the renal tubules, with mononuclear inflammatory cells, formation of papilliform structure projecting into the tubular lumen and metaplasia of the epithelium of the collecting tubule walls, from simple cubic in the tubules uninfected to pseudostratified in infected kidney with P. bragai. The eggs are elliptical, with operculum at the anterior end and a knot at the posterior end, abopercular region. The eggshell is rough and composed of three layers: inner, middle and outer with thicknesses and different electrondense. The miracidium is elongated, with terebratorium the anterior end and body covered with cilia. The cercariae have cylindrical body that tapers slightly in the posterior region. The tegument is rough, the oral sucker is subterminal, the acetabulum stands in the middle third of the body. Papillae were observed around the oral sucker. A similar rudimentary tail structure was observed in some cercariae. The metacercariae observed through histological sections visualized the oral sucker, acetabulum, scales and cyst that consist of three layers, inner, middle and outer, of different thicknesses. The presence of the layers was confirmed by visualization of histological sections of metacercariae in scanning electron microscopy. The adult parasite is elongated and flattened body with oral sucker, pharynx, vitelline glands extending to the region of cecal bifurcation and then the median region of the body. The genital pore visualized a structure that is everted the cirrus in rosette form. In the adult stage the tegument is covered with scales of various types; simple scales, with two, three, four, five and seven divisions, a characteristic that may contribute to ratify the taxonomic classification of the parasite. / Paratanaisia bragai ? um digen?tico que atinge a maturidade sexual nos ductos coletores de aves dom?sticas e silvestres, e para o desenvolvimento larval utiliza o molusco Subulina octona ou Leptinaria unilamellata. Os ovos embrionados s?o liberados com os produtos de excre??o do hospedeiro definitivo e a infec??o no molusco se estabelece pela ingest?o destes. Ap?s a eclos?o do mirac?dio, desenvolvem-se no interior do molusco duas gera??es de esporocistos, cerc?rias e metacerc?rias. O hospedeiro definitivo adquire a infec??o por ingest?o do molusco parasitado. O presente estudo teve como objetivos: verificar a a??o do parasito sobre o rim de pombos, Columba livia, atrav?s da an?lise histopatol?gica bem como analisar a morfometria, morfologia e ultraestrutura utilizando a microscopia de luz, eletr?nica de varredura e transmiss?o do ovo, est?gios larvais (mirac?dio, cerc?ria e metacerc?ria) e helminto adulto de P. bragai. Pombos adultos foram obtidos pr?ximos a Central de Abastecimento do Estado do Rio de Janeiro S.A, Iraj?, Munic?pio Rio de Janeiro. Ap?s exame coproparasitol?gico, no laborat?rio, para verifica??o da infec??o, os pombos infectados foram necropsiados para a coleta dos helmintos e do rim infectado. Os pombos n?o infectados foram utilizados como grupo controle. Os protocolos experimentais foram aprovados pela comiss?o de ?tica na pesquisa da UFRRJ. A an?lise histopatol?gica revelou dilata??o dos t?bulos renais, processo inflamat?rio com c?lulas mononucleadas, forma??o de estrutura papiliforme projetando-se para a luz tubular e metaplasia do epit?lio da parede do t?bulo coletor, de epit?lio c?bico simples nos t?bulos n?o infectados a pseudroestratificado nos rins infectados com P. bragai. Os ovos s?o el?pticos, com op?rculo na extremidade anterior e n? na extremidade posterior, regi?o abopercular. A casca apresenta-se ?spera e composta por tr?s camadas: interna, m?dia e externa de espessuras e eletrondensidades diferentes. O mirac?dio ? alongado, com terebratorium na extremidade anterior e corpo coberto por c?lios. As cerc?rias apresentam corpo cil?ndrico que se afunila ligeiramente na regi?o posterior. O tegumento ? rugoso, a ventosa oral ? subterminal, o acet?bulo destaca-se no ter?o m?dio do corpo. Papilas foram verificadas ao redor da ventosa oral. Uma estrutura semelhante ? cauda rudimentar foi observada em algumas cerc?rias. Nas metacerc?rias observadas atrav?s de cortes histol?gicos visualizou-se a ventosa oral, o acet?bulo, as escamas e cisto composto por tr?s camadas, interna, m?dia e externa, de espessuras diferentes. A presen?a das camadas foi confirmada na visualiza??o dos cortes histol?gicos das metacerc?rias na microscopia eletr?nica de varredura. O parasito adulto tem corpo alongado e achatado com ventosa oral, faringe, gl?ndulas vitelog?nicas extracecais que se prolongam anteriormente at? a regi?o de bifurca??o cecal e posteriormente a regi?o mediana do corpo. No poro genital visualiza-se uma estrutura evertida que ? o cirro em formato de roseta. No est?gio adulto o tegumento ? coberto por escamas de v?rios tipos; escamas simples, b?fidas, tr?fidas, com quatro, cinco e sete divis?es, caracter?stica que pode contribuir para ratificar a classifica??o taxon?mica do parasito.
22

Multimodal image registration in 2D and 3D correlative microscopy / Recalage d'images multimodales en microscopie corrélative 2D et 3D

Toledo Acosta, Bertha Mayela 23 May 2018 (has links)
Cette thèse porte sur la définition d'un schéma de recalage automatique en microscopie corrélative 2D et 3D, en particulier pour des images de microscopie optique et électronique (CLEM). Au cours des dernières années, la CLEM est devenue un outil d'investigation important et puissant dans le domaine de la bio-imagerie. En utilisant la CLEM, des informations complémentaires peuvent être collectées à partir d'un échantillon biologique. La superposition des différentes images microscopiques est généralement réalisée à l'aide de techniques impliquant une assistance manuelle à plusieurs étapes, ce qui est exigeant et prend beaucoup de temps pour les biologistes. Pour faciliter et diffuser le procédé de CLEM, notre travail de thèse est axé sur la création de méthodes de recalage automatique qui soient fiables, faciles à utiliser et qui ne nécessitent pas d'ajustement de paramètres ou de connaissances complexes. Le recalage CLEM doit faire face à de nombreux problèmes dus aux différences entre les images de microscopie électronique et optique et leur mode d'acquisition, tant en termes de résolution du pixel, de taille des images, de contenu, de champ de vision et d'apparence. Nous avons conçu des méthodes basées sur l'intensité des images pour aligner les images CLEM en 2D et 3D. Elles comprennent plusieurs étapes : représentation commune des images LM et EM à l'aide de la transformation LoG, pré-alignement exploitant des mesures de similarité à partir d'histogrammes avec une recherche exhaustive, et un recalage fin basé sur l'information mutuelle. De plus, nous avons défini une méthode de sélection robuste de modèles de mouvement, et un méthode de détection multi-échelle de spots, que nous avons exploitées dans le recalage CLEM 2D. Notre schéma de recalage automatisé pour la CLEM a été testé avec succès sur plusieurs ensembles de données CLEM réelles 2D et 3D. Les résultats ont été validés par des biologistes, offrant une excellente perspective sur l'utilité de nos développements. / This thesis is concerned with the definition of an automated registration framework for 2D and 3D correlative microscopy images, in particular for correlative light and electron microscopy (CLEM) images. In recent years, CLEM has become an important and powerful tool in the bioimaging field. By using CLEM, complementary information can be collected from a biological sample. An overlay of the different microscopy images is commonly achieved using techniques involving manual assistance at several steps, which is demanding and time consuming for biologists. To facilitate and disseminate the CLEM process for biologists, the thesis work is focused on creating automatic registration methods that are reliable, easy to use and do not require parameter tuning or complex knowledge. CLEM registration has to deal with many issues due to the differences between electron microscopy and light microscopy images and their acquisition, both in terms of pixel resolution, image size, content, field of view and appearance. We have designed intensity-based methods to align CLEM images in 2D and 3D. They involved a common representation of the LM and EM images using the LoG transform, a pre-alignment step exploiting histogram-based similarities within an exhaustive search, and a fine mutual information-based registration. In addition, we have defined a robust motion model selection method, and a multiscale spot detection method which were exploited in the 2D CLEM registration. Our automated CLEM registration framework was successfully tested on several real 2D and 3D CLEM datasets and the results were validated by biologists, offering an excellent perspective in the usefulness of our methods.
23

Numerické metody zpracování obrazů z mikroskopu s rotujícím kondenzorem. / Numerical image processing methods for rotating condenser microscope images processing

Týč, Matěj January 2008 (has links)
Tato práce popisuje vznik obrazu v transmisním světelném mikroskopu s proměnnou aperturou kondenzoru. Tento způsob pořizování obrazu je výhodný při pozorování tlustých vzorků, což jsou objekty, u kterých je v mikroskopickém měřítku významná výška. Klasické transmisní mikroskopy pro tento výzkum vhodné nejsou, protože výsledný obraz, který produkují, obsahuje patrné informace z velkého objemu vzorku mimo oblast, která je vyšetřovaná. Tento problém byl vyřešen po vynálezu konfokálního mikroskopu, který je ovšem daleko dražší a má i některé nevýhody navíc. Cílem je zpracovat obrazy pořízené pomocí kondenzoru s rotující aperturou tak, aby došlo k redukci podílu nežádoucí informace a obraz se tak stal "čistším". Tato metoda zpracování obrazu nemohla být použita v minulosti, protože tehdejší počítače neměly dostatečnou paměť a výkon. Na tuto metodu se dá nahlížet jako na převod množiny výstupů z mikroskopu s vylepšenou osvětlovací soustavou na odpovídající množinu výstupů konfokálního mikroskopu.
24

Evidence for a Unique Elastic Sheath Surrounding the Vesicular Arteries of the Rabbit Urinary Bladder - Studies of the Microvasculature With Microscopy and Vascular Corrosion Casting

Hossler, Fred E., Monson, Frederick C. 01 November 1998 (has links)
Because the urinary bladder stores and releases urine, its normal function includes filling and emptying, accompanied by distension and relaxation. It is known that chronic distension compromises blood flow. Recent studies of the rabbit bladder vasculature have described specializations of that vasculature that appear to enhance blood flow in the bladder wall during distension. The present report describes the location, orientation, and structure of an elastic sheath surrounding the vesicular arteries, which may represent one of these specializations. The location, vasculature, and structure of an accessory elastic sheath surrounding the vesicular arteries of the rabbit bladder is described using light and electron microscopy, India ink injection, and vascular corrosion casting. The common iliac arteries of rabbits were cannulated to permit perfusion of the distal vasculature including the urinary bladder. After the bladder vasculature was visually cleared of blood by perfusion with buffered saline, one of the following procedures was used: 1) for light or electron microscopy, the bladder was perfuse-fixed with buffered 2% glutaraldehyde; 2) the bladder vasculature was filled with India ink for vessel tracing; or 3) corrosion casts of the bladder vasculature were prepared by infusion of a Mercox resin mixture. Casts, cleaned of tissue with KOH, and water and formic acid rinses, are dried, and mounted for routine scanning electron microscopy. The presence of an accessory sheath surrounding the main vesicular arteries and some of their branches in the basal two thirds of the urinary bladder was observed on India ink injected specimens and confirmed by micrographs and vascular corrosion casts. The sheath consists of elastic and collagenous fibers and is separated from the tunica media of the arteries by a loose connective tissue layer of variable width. The sheath is circumscribed by a layer of fine blood vessels. The vesicular arteries undulate within the sheath to an extent which is dependent upon the degree of distension of the bladder. This sheath likely represents a specialization which permits the bladder vasculature to accommodate expansion and contraction of the wall during normal filling and emptying. Undulations or coiling of the vesicular arteries within the loose connective tissue core of the sheath increase with bladder contraction, and apparently the sheath simply holds the artery in position during such coiling. The sheath, may represent a modification of the external elastic lamina found in some muscular arteries.
25

The structure and function of the attachment organs in Cotylurus variegatus Creplin, 1825 (Odening, 1969) (Trematoda: Strigeida).

Haight, Murray Ellis 10 1900 (has links)
<p> Previous studies dealing with the structure and function of the attachment organs in the strigeid trematodes have neglected to describe the processes involved in the formation of attachment. A knowledge of these processes is necessary to promote the understanding of the host-parasite relationship. </p> <p> In the present study, specimens of developing Cotylurus variegatus were examined using light and electron microscopic techniques. It seemed relevant to consider not only the sequence of attachment events, but the growth and structure of the attachment organs in relation to the total parasite body growth and structure. This of course, has led to considerations of the reputative functions of these structures. </p> / Thesis / Master of Science (MSc)
26

A brief history of light microscopy applied to Portland cement clinker

Böhm, Matthias 31 July 2024 (has links)
The application of microscopic methods to raw materials, clinker, cement and hydrated cementitious systems has contributed significantly to the understanding of the chemical and mineralogical composition of clinker, its formation conditions and hydration reactions over the last 140 years. This publication reviews the contributions of important microscopists, the development of the method and the main issues addressed by light microscopy applied to Portland cement clinker.
27

Parietal cell regeneration in rat gastric mucosal wounds : a quantitative light and electron microscopical study

Blom, Håkan January 1982 (has links)
The aims of the study were to obtain a method with which it would be possible to produce standardized wounds in the gastric mucosa, and to follow the regeneration of the acid producing parietal cells in those lesions during different experimental conditions. Quantitative methods applied to light and electron microscopy were used. Wounds were cauterized in the corpus mucosa in Sprague-Dawley rats and in addition, pyloroplasty, truncal vagotomy with pyloroplasty or ant- rectoiriy were performed. Other groups of rats with wounds were given long-term treatment with pentagastrin or cimetidine. Stimulation tests were carried out in two groups of wound operated rats. After different periods of time the animals were perfusion fixed and specimens from the wounds and normal mucosa beside the wounds were pre­pared for light and electron microscopy. By means of stereological techniques, different mucosal and cellular structures were then measur­ed. Parietal cells were found in 90 days old wounds. At this stage they were immature with large nuclei and few specialized cell organelles. In spite of this appearance they were able to respond morphologically to stimulation and to secrete acid. With further healing the morphology of the parietal cells became normal, but their volume fraction in the mucosa remained subnormal. The fraction of mucosa occupied by epithel­ial cells also stayed lower than normal. Pyloroplasty resulted in decreased cell and nuclear size of both normal and regenerating parietal cells. In the latter, there was also a de­crease in the mitochondrial volume density. If a truncal vagotomy was added to the pyloroplasty these changes disappeared and, in addition, an increase in parietal cell volume density was noticed in the normal mucosa. Antrectorny produced smaller parietal cells, and their maturation was delayed. Furthermore, mucosal thickness decreased. If pentagastrin was given to rats with wounds an increase in the number of parietal cells was noted, but maturation and morphology remained unaffected. Cimetidine treatment did not affect the parietal cell volume density in wounds or normal mucosa. However, a large increase in the secretory surface density was noticed when the effect of the last dose had ceas­ed. / <p>S. 1-45: sammanfattning, s. 47-121 utgörs av 5 uppsatser</p> / digitalisering@umu
28

Molecular characterization of human vaginal mucosa obtained from fresh harvest and implants in an experimental nude mouse model

Kok, Cornelius Wilhelmus 03 1900 (has links)
Thesis (MMedSc )--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The present study investigated in particularly the specific nature of the supporting stromal layer located between the implanted human cyst and host murine tissue, which has yet to be reported. During an initial phase of this study, the particular light microscopic properties of the existing hematoxylin and eosin (H&E) stained experimental cyst was investigated, with regards to the presence or absence of specific morphological features, namely spongiosis, exocytosis, epithelial keratinization, epithelial thickness and hyperplasia, and the vascularity and fibrosis present in the stroma of these experimental sections. Subsequent analysis reported significant spongiosis, in addition to increased exocytosis of immune cells and epithelial keratinization in a number of cysts. Additionally, increased epithelial thickness and hyperplasia was reported in only 2 / 10 experimental tissues, whereas increased vascularity was observed in the stroma following analysis of H&E and Special staining, such as Verhoeff-von Gieson and Masson trichrome results. During the second phase of the study, immunohistochemical analysis with a particularly wide array of antibodies raised against specific human and mouse antigens had been applied. This involved automated immunohistochemical staining with mouse anti-human primary antibodies, in addition to manual staining with rabbit anti-mouse primary antibodies. Subsequent visualization was achieved by means of linking to biotinylated secondary antibodies, and Streptavidin-HRP incubation for standard visualization, followed by counterstaining with Hematoxylin. Maintained positive expression of cytokeratins 5, 13, and 14 was demonstrated in both control human vaginal mucosa and experimental cysts, whereas similar findings were not reported for cytokeratin 1, given the vast keratinization which was observed. Human collagen type IV and laminin of the basement membrane reported positive expression in 9 / 10 and 6 / 10 control human vaginal mucosa tissues respectively. In comparison, negative mouse collagen type IV and laminin was reported in most experimental cysts compared to positive staining in positive control mouse tissues. Immunohistochemical staining for human elastin, fibronectin, von Willebrand factor, and fibroblasts revealed maintained positive staining in all control human vaginal mucosa and experimental cysts. However, maintained expression of CD34 (endothelial marker), CD1a (langerhans cells), and human VEGFR-3 in experimental cysts was not demonstrated, compared to positive expression in control human vaginal mucosa. Subsequent analysis of murine antigens illustrated uniformly negative staining for mouse fibronectin, langerhans cells (CD207), and fibroblasts, in addition to negative staining in positive control mouse tissue sections. Furthermore, negative staining for mouse VEGFR-2 was reported in all experimental cysts; however strong positive staining of this marker in mouse kidney tissue had been reported. The findings of this study suggested that the exact nature of the stromal layer is of both human and murine origin. Furthermore, the tissue region located beneath the human vaginal epithelium is suggested to be of human nature, whereas the second distinct region located at the periphery of experimental cyst tissues, is suggested to be murine origin; however the findings of immunohistochemical analysis could not illustrate definitively the exact nature of the intermediate stromal layer, but could in fact demonstrate a mixture of human and murine tissue. / AFRIKAANSE OPSOMMING: Die huidige studie het die spesifieke molekulêre en histologiese eienskappe van die stromale laag geleë tussen menslike sist- en muis velweefsel bestudeer, wat tans nog nie bekend is nie. Gedurende die eerste fase van hierdie studie is die besondere lig-mikroskopiese eienskappe van die bestaande hematoksilien en eosien (H&E) eksperimentele siste bestudeer, met betrekking tot die aan- of afwesigheid van spesifieke morfologiese eienskappe, naamlik spongiose, eksositose van immuunselle, epiteel keratinisasie, epiteel dikte en hiperplasie, en laastens die stromale vaskulariteit en fibrose. Gevolglike analise het daarop gedui dat beduidende spongiose, eksositose en epiteel keratinisasie gevind word in die eksperimentele siste in vergelyking met kontrole vaginal weefsel. Hierteenoor is die verdikking van die epiteel en hiperplasie in slegs 2 / 10 eksperimentele siste gevind, terwyl vermeerderde vaskulariteit aangedui is na gevolglike H&E en spesiale (soos byvoorbeeld Verhoeff-von Gieson en Masson trichrome) kleuringsresultate. Die tweede fase van die studie het die immunokleuring met verskeie mens- en muis spesifieke antiliggame behels, waarby die uitdrukking van verskeie mens antigene vergelyk is met dié van muis. As sulks is ge-automatiseerde immunohistochemie toegepas met muis primêre antiliggame, tesame met fisiese kleuring met konyn primêre antiliggame toegepas. Gevolglike visualisasie is aangedui deur middel van binding met sekondêre antiliggaam en Streptavidin- HRP, gevolg deur teenkleuring met Hematoksilien. Algehele behoud van positiewe uitdrukking van sitokeratien 5, 13, en 14 is bevind, terwyl sitokeratien 1 uitdrukking nie daarwerklik vergelykbaar is met dié van kontrole mens vaginale weefsel nie. Die uitdrukking van mens kollageen IV en laminien van die basaal membraan is verder bestudeer, en het egter positiewe kleuring in 9 / 10 en 6 / 10 van kontrole mens vaginale mukosa aangedui. In vergelykking hiermee kon die huidige bevindings egter net positiewe kleuring in 4 / 10 en 3 / 10 eksperimentele siste vir kollageen IV en laminien onderskeidelik, illustreer. Immunohistochemiese analise van menslike elastien, fibronektien, von Willebrand (vW) faktor en fibroblaste het op deurgaans positiewe uitdrukking van hierdie merkers aangedui in beide eksperimentele en kontrole menslike weefsel. In teenstelling hiermee is volgehoue uitdrukking van CD34 (endoteel merker), CD1a (Langerhans sel merker) en mens VEGFR-3 in ekperimentele siste egter nie illustreerbaar nie, in vergelykking met deurgaans positiewe uitdrukking van hierdie antigene in kontrole mens vaginale mukosa. In opvolging is deurgaans negatiewe uitdrukking van muis fibronektien, langerhans sel (CD207) en fibroblaste bevestig, terwyl negatiewe kleuring ook deurgaans in positiwe kontrole muis weefsel, bekom deur die disseksie van ‘n naakte muis, gevind is. Verder is ook negatiewe kleuring vir VEGFR-2 in alle eksperimentele siste gevind, terwyl egter sterk positiewe kleuring in muis nierweefsel as positiewe weefsel gevind is. Die resultate van die huidige studie het daarop gedui dat die stromale laag onderliggend tot mens vaginale epiteel van menslike oorsprong is, terwyl die periferale stroma onderliggend tot muis velweefsel, ongetwyfeld van muis oorsprong is. Laastens kon die spesifieke oorsprong van die tussenliggende stroma nie aangedui word nie, maar dat dit moontlik uit beide menslike- en muisweefsel bestaan.
29

Vergleichende lichtmikroskopische Untersuchung von gesundem und erkranktem parodontalem Ligament (PDL) des Menschen / Light microscopic study of human periodontal ligament (PDL) by comparing healthy and disseased tissue

Schories, Hauke 16 September 2014 (has links)
No description available.
30

OMX - a novel high speed and high resolution microscope and its application to nuclear and chromosomal structure analysis

Haase, Sebastian 07 March 2008 (has links)
Im Rahmen dieser Arbeit wurde ein neuartiges 3D Fluoreszenz Mikroskop, OMX gennant, entworfen und gebaut. Ein umfassender Design-Neuansatz erlaubt es den neuen Anforderungen der aktuellen Biologie bezüglich erhöhter Auflösung in Zeit und Raum Rechnung zu tragen. Mit Ausnahme vom Auflegen des Objektträgers sind alle Aspekte des Mikroskops Computer-gesteuert. Einen Großteil der Software floß in ein neues, eigenständiges Open-Source Projekt ein. Es erlaubt die Verarbeitung sehr großer, mehrdimensionaler Bilddaten, und die Entwicklung neuartiger Algorithmen in einer flexiblen Oberfläche. OMX hat zwei Betriebsarten: Im ersten Modus können bis zu 100 Bilder pro Sekunde mit optischer Auflösung in mehreren Farbkanälen aufgenommen werden. Dies entspricht etwa 10 3D Bildern pro Sekunde. Im zweiten Modus können mit der Structured Illumination Mikroskopie fixierte Präparate mit eine Auflösung unterhalb des Abbe-Limits untersucht werden. Im zweiten Teil dieser Arbeit, stelle ich erste Forschungsergebnisse von OMX vor. Drosophila X-chromosomen markiert mit GFP-MSL3 wurden in situ im sub-Sekunden Bereich beobachtet. Mit Hilfe neuentwickelter Algorithmen konnte ich die Chromosomendynamik analysieren. Das Falten und Entfalten von Bereichen eines Chromosoms wurde als Funktion der Zeit darstellen. Chromosomenstrukturen wurden mit Hilfe der SIM an fixierten primären embryonalen Kulturen untersucht. Unterstrukturen von 100-200nm sind erkennenbar. Viele Bilder zeigen eine DNA-reiche Hülle die einen DNA-armen Chromosomenkern umgibt. Ausserdem habe ich polytäne Chromosomen mit SIM aufgenommen. Bandstrukturen zeigen sich mit deutlich erhöhter Detailklarheit, und Längsfasern sind sichtbar, die ansonsten nur vom Elektronenmikroskop her bekannt sind. Als weiteres Beispiel der verbesserten Auflösungsfähigkeit habe ich Kernporen untersucht. In mit DAPI gefärbten Mauszellen zeigen diese sich als dunkle Punkte mit einer Größe von etwa 120nm. / A novel fluorescence 3D wide-field light microscope called OMX, was designed and implemented. The novel design addresses improved speed and resolution requirements of current biology research. After designing and building the microscope body I designed and implemented the needed computer software for the eight computers required to operate OMX. Over the course of the project I also designed and implemented a new Open-Source software platform for algorithm development and image analysis. It focuses on very large multi-dimensional image data handling and visualization in general. OMX can operate in two modes: In the first mode a live specimen can be observed at optical resolution (approx. 250nm) at speeds up to 100 sections per second simultaneously in multiple wavelength channels. This equals about 10 3D images per second. The second mode is for observing fixed preparations at resolutions below the Abbe diffraction limit using Structured Illumination Microscopy (SIM). This produces 3D volumetric image data with lateral resolution near 100nm and axial resolution of about 200nm. In the second part of this thesis I show first results achieved using the OMX microscope. Chromosome dynamics was analyzed using various newly developed image analysis algorithms. Sub-second motion was observed for in situ Drosophila X-chromosomes tagged with GFP-MSL3. Parts of the chromosome can be traced within the nucleus and time-series data shows its folding and unfolding as a function of time. Chromosome structure was imaged using SIM on formaldehyde fixed primary embryonic cultures stained with DAPI. Features of the sub-structure with sizes around 100-200nm were apparent. Many chromosomes show an outer layer along the chromatin axis appearing persistently denser in DNA than the central core. Polytene chromosomes were imaged using SIM. Band patterns are visible in much more detail than in conventional deconvolution microscopy and longitudinal fibers known only from electron microscopy were visible.

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